Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.18926/AMO/65970.

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.18926/AMO/65971.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Abstract

The purpose of this study was to assess the associations between delivery room intubation (DRI) and severe intraventricular hemorrhage (IVH), as well as other neonatal outcomes, among extremely preterm infants without low Apgar scores using data from a large-scale neonatal registry data in Japan. We analyzed data for infants born at 24–27 gestational weeks between 2003 and 2019 in Japan using robust Poisson regression. Infants with low Apgar scores (≤ 1 at 1 min or ≤ 3 at 5 min) were excluded. The primary outcome was severe IVH. Secondary outcomes were other neonatal morbidities and mortality. The full cohort included 16,081 infants (intubation cohort, 13,367; no intubation cohort, 2714). The rate of DRI increased over time (78.6%, 2003–2008; 83.4%, 2009–2014; 87.8%, 2015–2019), while the rate of severe IVH decreased (7.1%, 2003–2008; 5.7%, 2009–2014; 5.3%, 2015–2019). Infants with DRI had a higher risk of severe IVH than those without DRI (6.8% vs. 2.3%; adjusted risk ratio, 1.86; 95% confidence interval, 1.33–2.58). The results did not change substantially when stratified by gestational age. Despite conflicting changes over time in DRI and severe IVH, DRI was associated with an increased risk of severe IVH among extremely preterm infants in Japan.

DOI： 10.1038/s41598-023-41010-x

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Other Link： https://www.nature.com/articles/s41598-023-41010-x

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Epidemiological Association  

DOI： 10.2188/jea.je20230034

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s00431-023-05062-5.

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Abstract

Chronic kidney disease (CKD) is a major global public health problem. Recent studies reported that diabetes and prediabetes are risk factors for developing CKD; however, the exact glycated hemoglobin (HbA1c) cut-off value for prediabetes remains controversial. In this study, we aimed to examine the relationship between HbA1c levels and subsequent CKD development in greater detail than previous studies. Longitudinal data of annual checkups of 7176 Japanese non-diabetic people (male: 40.4%) from 1998 to 2022 was analyzed. HbA1c values were categorized into < 5.0%, 5.0–5.4%, 5.5–5.9%, and 6.0–6.4%. CKD was defined as an estimated glomerular filtration rate < 60 ml/min/1.73 m². The descriptive statistics at study entry showed that higher HbA1c values were associated with male, older, overweight or obese, hypertensive, or dyslipidemic people. During a mean follow-up of 7.75 person-years, 2374 participants (male: 40.0%) developed CKD. The Weibull accelerated failure time model was selected because the proportional hazards assumption was violated. The adjusted time ratios of developing CKD for HbA1c levels of 5.5–5.9% and 6.0–6.4% compared with 5.0–5.4% were 0.97 (95% confidence interval: 0.92–1.03) and 1.01 (95% confidence interval: 0.90–1.13), respectively. There was no association between HbA1c in the prediabetic range and subsequent CKD development.

DOI： 10.1038/s41598-023-40300-8

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Other Link： https://www.nature.com/articles/s41598-023-40300-8

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Okayama University Medical School  

DOI： 10.18926/amo/65749

CiNii Books

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/fampra/cmad074.

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jtcvs.2023.07.003.

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1186/s12889-023-16228-z.

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1177/1357633X231181632.

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1089/jicm.2023.0077.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Abstract

Background

Extracorporeal cardiopulmonary resuscitation (ECPR) is rapidly becoming a common treatment strategy for patients with refractory cardiac arrest. Despite its benefits, ECPR raises a variety of ethical concerns when the treatment is discontinued. There is little information about the decision to withhold/withdraw life-sustaining therapy (WLST) for out-of-hospital cardiac arrest (OHCA) patients after ECPR.

Methods

We conducted a secondary analysis of data from the SAVE-J II study, a retrospective, multicenter study of ECPR in Japan. Adult patients who underwent ECPR for OHCA with medical causes were included. The prevalence, reasons, and timing of WLST decisions were recorded. Outcomes of patients with or without WLST decisions were compared. Further, factors associated with WLST decisions were examined.

Results

We included 1660 patients in the analysis; 510 (30.7%) had WLST decisions. The number of WLST decisions was the highest on the first day and WSLT decisions were made a median of two days after ICU admission. Reasons for WLST were perceived unfavorable neurological prognosis (300/510 [58.8%]), perceived unfavorable cardiac/pulmonary prognosis (105/510 [20.5%]), inability to maintain extracorporeal cardiopulmonary support (71/510 [13.9%]), complications (10/510 [1.9%]), exacerbation of comorbidity before cardiac arrest (7/510 [1.3%]), and others. Patients with WLST had lower 30-day survival (WLST vs. no-WLST: 36/506 [7.1%] vs. 386/1140 [33.8%], p < 0.001). Primary cerebral disorders as cause of cardiac arrest and higher severity of illness at intensive care unit admission were associated with WLST decisions.

Conclusion

For approximately one-third of ECPR/OHCA patients, WLST was decided during admission, mainly because of perceived unfavorable neurological prognoses. Decisions and neurological assessments for ECPR/OHCA patients need further analysis.

DOI： 10.1186/s13054-023-04534-2

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Other Link： https://link.springer.com/article/10.1186/s13054-023-04534-2/fulltext.html

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3390/ijerph20126173.

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Language：English   Publishing type：Research paper (scientific journal)  

Involuntary exposure to tobacco smoke is suspected to be one of the risks factors that are associated with obesity in children. The purpose of this study was to examine the relationship between early childhood exposure to tobacco smoke and the risk of obesity and overweight in Japan. This study utilized a nationwide, population-based longitudinal survey. The participants were restricted to 32 081 children who had available information on maternal smoking history as well as childhood height and weight. We conducted a binomial log-linear regression analysis with children of non-smoking mothers as the reference group. The children with mothers who were smokers had a higher risk of developing obesity or being overweight compared to the children with mothers who were nonsmokers. The risk ratios were 1.20 (95% confidence interval [CI]: 1.09-1.32) for overweight and 1.17 (95% CI: 0.95-1.44) for obesity. Early exposure to maternal smoking increases the risk of being overweight and having obesity during childhood. The increased risk is more pronounced among children with mothers, smoked heavily, or parents, who were smokers.

DOI： 10.1111/cob.12572

PubMed

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1186/s13030-023-00278-1.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Ovid Technologies (Wolters Kluwer Health)  

DOI： 10.1097/pcc.0000000000003206

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.31662/jmaj.2022-0122.

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.archger.2022.104906

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.18926/AMO/65148

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3389/fped.2023.1127053.

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1161/JAHA.122.027046.

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Epidemiological Association  

DOI： 10.2188/jea.je20220265

PubMed

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

Introduction: It is recommended that users of complementary and alternative medicine (CAM) also seek conventional medical care to prevent the loss of access to appropriate medical care. However, the status of such use is unknown. The aim of this study was to examine the time trends in the proportion of CAM users who also receive conventional medical care for the same symptoms. Methods: This is a repeated cross-sectional study. Of data for 753,978 respondents to the Comprehensive Survey of Living Conditions, which was conducted seven times between 1995 and 2013, data from 17,707 individuals who used acupuncture, moxibustion, anma-massage-shiatsu, or judo therapy were analyzed. Cross-classified multilevel logistic regression models with individuals as level 1 and survey year and cohort as level 2 were used to calculate odds ratios (ORs) and 95% credible intervals (CIs) for combined use of CAM and conventional medical care. Age was entered as an individual-level variable. The period effect after 2003 was entered as a survey year-level variable because the number of eligible persons providing CAM treatments has increased since 2003. Results: Among the 17,707 CAM users, 11,567 (65.3%) were women. When age was entered as an explanatory variable, the results showed that both older men and women tended to receive conventional medical care (women, OR: 1.04, 95% CI: 1.03-1.04; men, OR: 1.03, 95% CI: 1.02-1.04). Additional examination of the possible period effect after 2003 showed a positive (although nonsignificant) association (women, OR: 1.36, 95% CI: 0.89-1.99; men, OR: 1.37, 95% CI: 0.94-1.91). Conclusions: As patient age increased, patients combined CAM use with conventional medicine. The findings also suggested that the combined use of CAM and conventional medicine has increased since 2003.

DOI： 10.1089/jicm.2022.0631

PubMed

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Abstract

In Japan, mean birth weight has significantly decreased from 3152 g in 1979 to 3018 g in 2010 and the prevalence of preterm birth (PTB) has risen to 5.7% in the last thirty years. However, the presence and magnitude of geographical differences in low birthweight (LBW) and/or PTB in Japan is not well understood. We implemented spatial analysis to identify localized clusters and hot spots of LBW and/or PTB during 2012–2016. The Japan national birth database was used in this study. A total of 5,041,685 (male: 2,587,415, female: 2,454,270) births were used for spatial analysis using empirical Bayes estimates of the incidence rate of LBW and/or PTB and spatial scan tests to detect hot-spot areas with p values calculated from Monte Carlo iterations. The most and second likely clusters were located in two areas: (1) the small islands in south-west Japan (Amami and Okinawa, Relative risk = 1.09–1.67 with p < 0.001) and (2) the cities on the base of Mt. Fuji, stretching over three neighboring prefectures of Yamanashi, Shizuoka and Kanagawa (Relative risk = 1.10–1.55 with p < 0.001), respectively. We need to optimize the medical resource allocations based on the evidence in geographical clustering of LBW and/or PTB at specific locations in Japan.

DOI： 10.1038/s41598-023-28642-9

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Other Link： https://www.nature.com/articles/s41598-023-28642-9

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.jiac.2022.09.012

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

AIM: A number of studies have indicated the potential benefits that breastfeeding has on reducing childhood obesity, but few studies have evaluated the effect on adolescent obesity. We examined the association between breastfeeding and overweight or obesity at 15 years of age using data from a large nationwide longitudinal study launched by the Japanese Government in 2001. METHODS: We analysed data for 26 164 participants with known infant feeding practices at 6 months of age, namely the duration of breastfeeding or formula feeding. Overweight or obesity at 15 years of age were calculated based on the subject's self-reported height and weight. Multinomial logistic regression analysis adjusted the data for child factors, namely sex, siblings, birth weight and physical activity clubs and the maternal factors of age, educational attainment and smoking status. RESULTS: Formula feeding was associated with an increased risk of overweight or obesity at 15 years of age. The adjusted odds ratios (95% confidence intervals) were 0.99 (0.89-1.09) for partial breastfeeding and 1.23 (1.02-1.48) for formula feeding, when exclusive breastfeeding was the reference category. CONCLUSION: Breastfeeding during infancy had potential benefits for overweight or obesity among 15-year-old adolescents. Our results provide further evidence of the importance of breastfeeding.

DOI： 10.1111/apa.16551

PubMed

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/19338244.2022.2047584

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3233/AJW230023

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Korean Geriatrics Society  

Background: Frailty is associated with the incidence of disability in older adults; however, few studies have investigated differences in the association of frailty with mild and severe disabilities according to Japanese long-term care insurance certification. This study separately investigated the associations between frailty and the incidence of mild and severe disabilities.Methods: This 3-year retrospective cohort study included community-dwelling adults in Okayama City aged ≥65 years. We assessed frailty status using the Kihon Checklist and defined the outcomes as mild and severe disabilities according to long-term care insurance certifications. We applied multinomial logistic regression analysis to investigate the association between frailty and the incidence of mild and severe disabilities.Results: The analysis included a total of 36,043 participants. For mild disability, the odds ratios (ORs) comparing frail to robust and prefrail to robust were 3.85 (95% confidence interval [CI], 3.36–4.42) and 1.82 (95% CI, 1.58–2.10), respectively. Similarly, the corresponding ORs for severe disability were 4.35 (95% CI, 3.55–5.34) and 1.78 (95% CI, 1.43–2.21), respectively. In the age-stratified analysis of mild disability, the pre-old group (aged 65–74 years) with frail showed a higher association than the old-age group (aged ≥75 years) with frail. Regarding severe disability, the older group with frailty showed a higher association than the pre-old group with frailty.Conclusion: The results showed that both prefrail and frail were associated with the incidence of mild and severe disabilities, with different patterns of association between the pre-old and old age groups.

DOI： 10.4235/agmr.22.0097

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Other Link： http://www.e-agmr.org/journal/view.php?doi=10.4235/agmr.22.0097

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2188/jea.JE20220210

PubMed

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.jaip.2022.09.024

PubMed

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Language：English   Publishing type：Research paper (scientific journal)  

Amid the Coronavirus Disease 2019 pandemic, we aimed to demonstrate the accuracy of the fingertip whole blood sampling test (FWT) in measuring the antibody titer and uncovering its dynamics shortly after booster vaccination. Mokobio SARS-CoV-2 IgM & IgG Quantum Dot immunoassay (Mokobio Biotechnology R&D Center Inc., MD, USA) was used as a point-of-care FWT in 226 health care workers (HCWs) who had received two doses of the BNT162b2 mRNA vaccine (Pfizer-BioNTech) at least 8 months prior. Each participant tested their antibody titers before and after the third-dose booster up to 14-days. The effect of the booster was observed as early as the fourth day after vaccination, which exceeded the detection limit (> 30,000 U/mL) by 2.3% on the fifth day, 12.2% on the sixth day, and 22.5% after the seventh day. Significant positive correlations were observed between the pre- and post-vaccination (the seventh and eighth days) antibody titers (correlation coefficient, 0.405; p < 0.001). FWT is useful for examining antibody titers as a point-of-care test. Rapid response of antibody titer started as early as the fourth day post-vaccination, while the presence of weak responders to BNT162b2 vaccine was indicated.

DOI： 10.1038/s41598-022-24464-3

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

Abstract

Objectives

The Glasgow‐Blatchford score (GBS) is a widely used risk assessment tool for patients with upper gastrointestinal bleeding. However, it only identifies a relatively low proportion of patients at low risk for adverse events and poor outcomes. We developed a simple diagnostic algorithm combining the GBS and nasogastric aspirate and evaluated its diagnostic performance.

Methods

A total of 115 consecutive patients with suspected nonvariceal upper gastrointestinal bleeding who underwent nasogastric tube placement and upper endoscopy at our emergency department were prospectively evaluated. We compared the diagnostic accuracy of the GBS and our algorithm for predicting high‐risk endoscopic lesions (HRELs) using receiver operating characteristic curve analysis.

Results

Thirty‐five patients had HRELs. Compared with the GBS, our algorithm showed superior performance with respect to the prediction of HRELs (area under the curve, 0.639 and 0.854, respectively; p &lt; 0.001). With set optimal threshold values, the algorithm identified a significantly higher proportion of patients who did not have HRELs than the GBS (23.5% vs. 2.6%, p &lt; 0.001).

Conclusions

The novel algorithm has improved the diagnostic performance of the GBS and predicted more patients who did not have HRELs than the GBS alone. After further validation, it may be a useful tool for making clinical management decisions for patients with nonvariceal upper gastrointestinal bleeding.

DOI： 10.1002/deo2.185

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Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/deo2.185

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.jiac.2022.07.002

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.jinf.2022.07.007

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Abstract

Background

Since 1996, many studies have reported that periodontal disease during pregnancy may be a risk factor for preterm birth and low birth weight; however, in Africa, periodontal disease is considered a non-high-priority disease. In addition, there are few dental facilities in rural Rwanda; thus, the oral condition of pregnant women has not been investigated. The objective of this study was to assess the tooth brushing habits of pregnant women in rural Rwanda and evaluate whether periodontal bacteria in the oral cavity of pregnant women are related to birth outcomes or oral cleaning habits.

Methods

A questionnaire survey and saliva collection were conducted for pregnant women in the catchment area population of Mibilizi Hospital located in the western part of Rwanda. Real-time PCR was performed to quantitatively detect total bacteria and 4 species of periodontal bacteria. The relationship of the copy number of each bacterium and birth outcomes or oral cleaning habits was statistically analyzed.

Results

Among the participants, high copy numbers of total bacteria, Tannerella forsythia, and Treponema denticola were correlated with lower birth weight (p = 0.0032, 0.0212, 0.0288, respectively). The sex ratio at birth was higher in women who had high copy numbers of Porphyromonas gingivalis and T. denticola during pregnancy (p = 0.0268, 0.0043). Furthermore, regarding the correlation between oral cleaning habits and the amount of bacteria, the more frequently teeth were brushed, the lower the level of P. gingivalis (p = 0.0061); the more frequently the brush was replaced, the lower the levels of P. gingivalis and T. forsythia (p = 0.0153, 0.0029).

Conclusions

This study suggested that improving tooth brushing habits may reduce the risk of periodontal disease among pregnant women in rural Rwanda. It also indicated that the amount of bacteria is associated with various birth outcomes according to the bacterial species. Both access to dental clinics and the oral cleaning habits of pregnant women should be important considerations in efforts to alleviate reproductive-related outcomes in rural Africa.

DOI： 10.1186/s12903-022-02443-4

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Other Link： https://link.springer.com/article/10.1186/s12903-022-02443-4/fulltext.html

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Research Square Platform LLC  

Abstract

BackgroundThe respiratory syncytial virus (RSV) disease burden is significant, especially in infants and patients with an underlying disease, and prophylaxis with palivizumab is recommended for these high-risk groups. Early recognition of a RSV epidemic is important for timely administration of palivizumab. We herein aimed to assess the correlation between national surveillance and Google Trends data pertaining to RSV infections in Japan.MethodsThe retrospective survey was performed between January 1, 2018, and November 14, 2021, and evaluated the correlation of national surveillance and Google Trends data. Joinpoint regression was used to analyze the data to evaluate the points at which changes in trends occurred. ResultsAs a result, a strong correlation was observed every study year (2018 [r=0.87, p&lt;0.01], 2019 [r=0.83, p&lt;0.01], 2020 [r=0.83, p&lt;0.01], and 2021 [r=0.96, p&lt;0.01]). The change-points in the Google Trends data indicating the start of the RSV epidemic in 2018 and 2021 were observed earlier than by sentinel surveillance and in 2019 and 2020 simultaneously with sentinel surveillance.ConclusionsOur data suggested that Google Trends has the potential to enable early identification of the RSV epidemic. In countries without a national surveillance system, Google Trends may serve as an alternative early warning system.

DOI： 10.21203/rs.3.rs-1332314/v1

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Failed internal fixations for trochanteric fractures have a strong negative impact owing to increased postoperative mortality and high medical costs. However, evidence on the prognostic value of postoperative radiographic findings for failed internal fixations is limited. We aimed to clarify the association between comprehensive immediate postoperative radiographic findings and failed internal fixation using relative and absolute risk measures. We followed the meta-analysis of observational studies in epidemiology guidelines and the Cochrane handbook. We searched specific databases in November 2021. The outcomes of interest were failed internal fixation and cut-out. We pooled the odds ratios and 95% confidence intervals using a random-effects model and calculated the number needed to harm for each outcome. Thirty-six studies involving 8938 patients were included. The certainty of evidence in the association between postoperative radiographic findings and failed internal fixation or cut-out was mainly low or very low except for the association between intramedullary malreduction on the anteromedial cortex and failed internal fixation. Moderate certainty of evidence supported that intramedullary malreduction on the anteromedial cortex was associated with failed internal fixation. Most postoperative radiographic findings on immediate postoperative radiographs for trochanteric fractures were uncertain as prognostic factors for failed internal fixations.

DOI： 10.3390/jcm11164879

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Oxford University Press (OUP)  

Abstract

Background

Patients with pneumoconiosis, such as silicosis and asbestosis, have a high risk of lung cancer. However, whether these patients are at high risk for neoplasms other than lung cancer and mesothelioma remains inconclusive.

Aims

To examine whether patients with pneumoconiosis have a higher incidence of malignant neoplasms other than lung cancer.

Methods

We conducted a cohort study using the medical records of patients with pneumoconiosis who visited our two hospitals from 1 January 1991 through 31 December 2017. We identified the occurrence of malignant neoplasms and calculated the incidences and standardized incidence ratios (SIRs) compared with those of the general population.

Results

One hundred and seventy patients with pneumoconiosis (163 men, 7 women) including 142 patients with silicosis, 24 with asbestosis and 4 with pneumoconiosis were identified. The mean age was 66.8 years. The proportion of smokers was 79%. Forty-seven malignant neoplasms occurred. Most malignant neoplasms were lung cancer (n = 22), while some were digestive cancers such as gastric cancer (n = 9), oesophageal cancer (n = 3) and colorectal cancer (n = 3). Participants presented increased risks for lung cancer (SIR: 10.86, 95% confidence interval [CI]: 7.15–16.49), gastric cancer (SIR: 2.55, 95% CI: 1.22–5.35) and oesophageal cancer (SIR: 5.78, 95% CI: 1.86–17.92).

Conclusions

Compared with the general population, patients with pneumoconiosis had an increased risk of malignant neoplasms of the digestive system in addition to lung cancer. Clinicians should consider testing for digestive system cancers as well as for lung cancers in these patients.

DOI： 10.1093/occmed/kqac011

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BACKGROUND: Previous studies showed that preterm birth increased the risk for hospital admissions in infancy and childhood due to some acute diseases. However, the risk of preterm children developing Kawasaki disease remains unknown. In the present study, we investigate whether preterm birth increased the morbidity of Kawasaki disease. METHODS: We included 36,885 (34,880 term and 2005 preterm) children born in 2010 in Japan. We examined the association between preterm birth and hospitalization due to Kawasaki disease using a large nationwide survey in Japan. RESULTS: In log-linear regression models that were adjusted for children's characteristics (sex, singleton birth, and parity), parental characteristics (maternal age, maternal smoking, paternal smoking, maternal education, and paternal income), and residential area, preterm infants were more likely to be hospitalized due to Kawasaki disease (adjusted risk ratio: 1·55, 95% confidence interval: 1.01-2.39). We then examined whether breastfeeding status modified the potential adverse effects of preterm birth on health outcome. Preterm infants with partial breastfeeding or formula feeding had a significantly higher risk of hospitalization due to Kawasaki disease compared with term infants with exclusive breastfeeding. CONCLUSIONS: Preterm infants were at a high risk for Kawasaki disease, and exclusive breastfeeding might prevent this disease among preterm infants. IMPACT: Previous studies showed that preterm birth increased the risk for hospital admissions in infancy and childhood due to some acute diseases, however, the risk of preterm children developing Kawasaki disease remains unknown. This Japanese large population-based study showed that preterm infants were at a high risk for Kawasaki disease for the first time. Furthermore, this study suggested that exclusively breastfeeding might prevent Kawasaki disease among preterm infants.

DOI： 10.1038/s41390-021-01780-4

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BACKGROUND: Children born preterm may be less physically active than children born term because of neurocognitive problems, reduced lung function, and poor physical fitness. We evaluated sports participation of children and adolescents who had been born preterm (<37 weeks) and early term (37-38 weeks) in 2001. METHODS: Data from a nationwide longitudinal survey (n = 47,015, including 2375 children born preterm) were analyzed. As indicators of sports participation, we used responses to questions about participation in sports clubs at 7 and 10 years old and in extracurricular school sports at 15 years old. RESULTS: Children born very preterm (25-31 weeks) and moderately to late preterm (32-36 weeks) were less likely to participate in sports clubs at 7, 10, and 15 years old than children born full term (39-41 weeks). Compared with children born full term, the adjusted risk ratios for participation in extracurricular school sports at 15 years old were 0.86 (95% confidence interval: 0.75-0.98) for children born very preterm, 0.92 (0.88-0.97) for children born moderately to late preterm, and 1.00 (0.98-1.02) for children born early term. CONCLUSIONS: Our findings suggest that preterm birth is associated with less participation in organized sports during childhood and adolescence than full-term birth. IMPACT: Research investigating associations between preterm birth and physical activity among children born in the 2000s is limited. This study shows that preterm birth was associated with less participation in organized sports during childhood and adolescence than full-term birth, especially in boys, and the participation in organized sports of children born preterm decreased as gestation shortened. During childhood, boys born early term were also less likely to participate in organized sports than boys born full term, suggesting a continuum with preterm births. These findings offer important additional insights into the limited evidence available for predicting future health outcomes for preterm infants.

DOI： 10.1038/s41390-021-01808-9

PubMed

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.18926/AMO/63903.

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.18926/AMO/63893

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.ajem.2022.05.017

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1007/s00431-022-04501-z

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Other Link： https://link.springer.com/article/10.1007/s00431-022-04501-z/fulltext.html

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：National Center for Global Health and Medicine (JST)  

DOI： 10.35772/ghm.2021.01125

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.resuscitation.2022.01.028

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Abstract

Background

Many epidemiological studies have reported the association between exposure to particulate matter and mortality, but long-term prospective studies from Asian populations are sparse. Furthermore, associations at low levels of air pollution are not well clarified. Here, we evaluated associations between long-term exposure to particulate matter &lt;2.5 µg/m³ (PM_2.5) and mortality in a Japanese cohort with a relatively low exposure level.

Methods

The Japan Public Health Center-based Prospective Study (JPHC Study) is a prospective cohort study of men and women aged 40-69 years in 1990 who were followed up through 2013 for mortality. In this cohort of 87,385 subjects who did not move residence during follow-up, average PM_2.5 levels from 1998 to 2013 by linkage with 1-km² grids of PM_2.5 concentration were assigned to the residential addresses of all participants. To avoid exposure misclassification, we additionally evaluated the association between 5-year (1998-2002) cumulative exposure level and mortality during the follow-up period from 2003 to 2013 in 79,078 subjects. Cox proportional hazards models were used to calculate the association of long-term exposure to PM_2.5 on mortality, with adjustment for several individual confounding factors.

Results

Average PM_2.5 was 11.6 µg/m³. Average PM_2.5 exposure was not associated with all-cause mortality or cancer and respiratory disease mortality. However, average PM_2.5 was positively associated with mortality from cardiovascular disease (hazard ratio (HR) of 1.23 (95%CI=1.08-1.40) per 1-µg/m³ increase; in particular, HR in mortality from cerebrovascular disease was 1.34 (95%CI=1.11-1.61) per 1-µg/m³ increase. Additionally, these results using cumulative 5-year PM_2.5 data were similar to those using average PM_2.5 over 15 years.

Conclusions

We found evidence for a positive association between PM_2.5 exposure and mortality from cardiovascular disease in a Japanese population, even in an area with relatively low-level air pollution.

DOI： 10.1186/s12889-022-12829-2

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Other Link： https://link.springer.com/article/10.1186/s12889-022-12829-2/fulltext.html

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Previous studies have not assessed the causal effect of the Olympic Games on the spread of pandemics. Using the synthetic control method and the national public city data in Japan recorded from February to September 2021, we estimated the causal effects of the Tokyo 2020 Olympic and Paralympic Games on the number of coronavirus disease 2019 (COVID-19) cases. The difference between the number of COVID-19 cases in Tokyo and a counterfactual “synthetic Tokyo” (created using synthetic control method) after the opening of the Tokyo 2020 Games (23 July 2021) widened gradually and then considerably over time. It was predicted that the Tokyo 2020 Games increased the number of COVID-19 cases in Tokyo by approximately 469.4 per 100,000 population from the opening of the event to 30 September. However, sensitivity analysis of the ratio of the pre- and post-game root mean square prediction errors using regression weights did not suggest robustness. Our results showed that the Tokyo 2020 Games probably increased the number of COVID-19 cases even under preventive regulations; however, the extent of this increase was difficult to estimate clearly due to an overlap with the fifth wave associated with the Delta variant.

DOI： 10.3390/jpm12020209

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Fuji Technology Press Ltd.  

COVID-19 has been prevalent worldwide since 2019. Increasing COVID-19 vaccination coverage is an important measure to combat the disease. An online survey was conducted with university students and personnel who were vaccinated against COVID-19 at a mass vaccination event to examine the factors promoting vaccination among young adults. The online survey was conducted with persons vaccinated at Okayama University from June 5 to September 27, 2021. Although the number of those who had fever &gt;37.5°C increased after the second vaccination compared to the first, the vaccinated persons got more satisfied after the second shot.

DOI： 10.20965/jdr.2022.p0021

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Medical Association  

DOI： 10.31662/jmaj.2021-0075

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BACKGROUND: Preschool children in Asian countries, including Japan, sleep for a shorter duration at night than those in Europe and the USA. We examined the effects of the nighttime sleep duration on behavioral development in early childhood in Japan. METHODS: We used data from a large Japanese nationwide, population-based, longitudinal survey that began in 2001. We restricted the study participants to children born after 37 gestational weeks, with a birth weight ≥ 2500 g and singleton births (n = 41 890). The nighttime sleep duration was examined at 2.5 years old. Responses to survey questions regarding age-appropriate behavior at 5.5 years old were used as indicators of behavioral development. We conducted logistic regression analyses with adjustment for confounding factors, with ≥11 h of nighttime sleep as the reference group. RESULTS: The odds ratios for children who had ≤9 h of nighttime sleep, which was associated with being unable to listen with fidgeting and being unable to remain patient, were 1.26 (95% confidence interval, 1.14-1.39) and 1.27 (1.16-1.38), respectively. Children who had an irregular nighttime sleep duration were associated with age-appropriate behavioral inabilities. These results were similar in children who usually and sometimes took naps to those before stratification by the frequency of napping. CONCLUSION: A short nighttime sleep duration especially affects hyperactivity and impulsivity. An irregular nighttime sleep duration increases the inability to perform overall age-appropriate behaviors more than a short sleep duration. Ensuring a regular and sufficient nighttime sleep duration in early childhood is important for healthy behavioral development.

DOI： 10.1111/ped.15354

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

Purpose: To perform a systematic review on the association between alcohol consumption and risk of age-related macular degeneration (AMD) using a meta-analytical approach.Method: Systematic literature research was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Both categorical and dose-response meta-analysis was performed separately for early and late AMD. A fixed-effect model was used to calculate pooled effect estimates with 95% confidence interval (CI).Result: Seven studies were included in the analysis with 4,566 and 440 cases of early and late AMD, respectively. Compared to the nondrinkers or occasional drinkers, the pooled effect estimates for early AMD with moderate (1.19, 95% CI [1.03-1.37]) and heavy (1.24, [1.10-1.39]) alcohol consumption, but not light (0.95, [0.90-1.06]) alcohol consumption, were statistically significant. However, the pooled effect estimates for late AMD with light (1.03, [0.79-1.33]), moderate (1.13, [0.83-1.55]), and heavy (0.98, [0.63-1.53]) alcohol consumption were found to be insignificant. A linear dose-response relationship was established (P < .05) between alcohol consumption and risk of early AMD, and the pooled effect estimate for an increase in alcohol consumption of 10 g/day was 1.14 (1.08-1.21).Conclusion: Moderate and heavy alcohol consumption could increase the risk of early AMD, but not late AMD, with a linear dose-response relationship.

DOI： 10.1080/02713683.2021.1942070

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To investigate the dynamics of body mass index (BMI) and height changes in childhood leading to obesity in adolescents. BMI Z-scores were calculated using the LMS (lambda-mu-sigma) method based on yearly height and weight information (age 1.5-15 years) from a nationwide Japanese birth cohort that started in 2001 (n = 26,711). We delineated the trajectories of BMI and height changes leading to obesity at age 15 years using mixed effect models. Children who became obese at the age of 15 years kept relatively high BMI z-scores through childhood for both genders, and had an increasing trend over time as opposed to the normal weight group, with an increasing slope during puberty. Early adiposity rebound was associated with overweight or obesity at the age of 15 years. Age at peak height velocity (APHV) occurred earlier in the obese/overweight group at age 15 years than in the normal weight group, and occurred later in the underweight group. Obese adolescents experienced early adiposity rebound timing and maintained a serial BMI z-score increase throughout childhood, with a greater slope at puberty. An earlier peak in height gain during puberty may have contributed to the observed patterns of BMI change.

DOI： 10.1038/s41598-021-02464-z

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Language：English   Publishing type：Research paper (scientific journal)  

The incidence of allergic diseases is increasing, and research on their epidemiology, pathophysiology, and the prevention of onset is urgently needed. The onset of allergic disease begins in infancy with atopic dermatitis and food allergy and develops into allergic asthma and allergic rhinitis in childhood; the process is defined as "atopic march". Atopic march is caused by multiple immunological pathways, including allergen exposure, environmental pollutants, skin barrier dysfunction, type 2 inflammation, and oxidative stress, which promote the progression of atopic march. Using recent evidence, herein, we explain the involvement of allergic inflammatory conditions and oxidative stress in the process of atopic march, its epidemiology, and methods for prevention of onset.

DOI： 10.3390/children8111067

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

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We examined the association between early childhood exposure to maternal smoking and behavioral issues at 8 years old using a large nationwide population-based longitudinal survey in Japan that began in 2001. We included 46,737 children with information about maternal smoking taken from the 6-month survey. We used logistic regression analysis to examine the hypothesis. Early childhood exposure to maternal smoking increased the risk of behavioral problems related to attention and aggressive or disruptive behavior. The adjusted odds ratios (95% confidence intervals) were 1.37 (1.22-1.54) for inability to wait their turn during play and 1.40 (1.27-1.55) for destroying toys and, compared with children of nonsmoking mothers. Children of mothers who were heavy smokers were more likely to develop behavioral problems than others. Stopping early childhood exposure to maternal exposure can protect children's neurodevelopment.

DOI： 10.1080/19338244.2021.1972278

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

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Language：English  

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Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

<title>Abstract</title>
<sec>
<title>Introduction</title>
The Helicopter Emergency Medical Service (HEMS) commonly intubates patients who require advanced airway support prior to takeoff. In-flight intubation (IFI) is avoided because it is considered difficult due to limited space, difficulty communicating, and vibration in flight. However, IFI may shorten the total prehospital time. We tested whether IFI can be performed safely by the HEMS.


</sec>
<sec>
<title>Methods</title>
We conducted a retrospective cohort study in adult patients transported from 2010 to 2017 who received prehospital, non-emergent intubation from a single HEMS. We divided the cohort in two groups, patients intubated during flight (flight group, FG) and patients intubated before takeoff (ground group, GG). The primary outcome was the proportion of successful intubations. Secondary outcomes included total prehospital time and the incidence of complications.


</sec>
<sec>
<title>Results</title>
We analyzed 376 patients transported during the study period, 192 patients in the FG and 184 patients in the GG. The intubation success rate did not differ between the two groups (FG 189/192 [98.4%] vs. GG 179/184 [97.3%], <italic>p</italic> = 0.50). There were also no differences in hypoxia (FG 4/117 [3.4%] vs. GG 4/95 [4.2%], <italic>p</italic> = 1.00) or hypotension (FG 6/117 [5.1%] vs. GG 5/95 [5.3%], <italic>p</italic> = 1.00) between the two groups. Scene time and total prehospital time were shorter in the FG (scene time 7 min vs. 14 min, <italic>p</italic> &lt;  0.001; total prehospital time 33.5 min vs. 40.0 min, <italic>p</italic> &lt;  0.001).


</sec>
<sec>
<title>Conclusions</title>
IFI was safely performed with high success rates, similar to intubation on the ground, without increasing the risk of hypoxia or hypotension. IFI by experienced providers shortened transportation time, which may improve patient outcomes.


</sec>

DOI： 10.1186/s13049-020-00784-z

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Other Link： http://link.springer.com/article/10.1186/s13049-020-00784-z/fulltext.html

Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.jpeds.2020.06.075

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Authorship：Lead author   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.scitotenv.2020.140465

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Language：English   Publishing type：Research paper (scientific journal)  

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.amsu.2020.07.062

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Authorship：Last author   Publishing type：Research paper (scientific journal)   Publisher：Mary Ann Liebert Inc  

DOI： 10.1089/bfm.2020.0064

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Other Link： https://www.liebertpub.com/doi/pdf/10.1089/bfm.2020.0064

Language：English   Publishing type：Research paper (scientific journal)  

The importance of centralizing treatment services for severely ill children has been well established, but such entralization remains difficult in Japan. We aimed to compare the trauma and illness severity and mortality of children admitted to two common types of ICUs for children. According to the type of management and disposition of the medical provider, we classified ICUs as pediatric ICUs [PICUs] or general ICUs, and analyzed differences in endogenous and exogenous illness settings between them. Overall, 1,333 pediatric patients were included, with 1,143 patients admitted to PICUs and 190 patients to general ICUs. The Pediatric Cerebral Performance Category score (PCPC) at discharge was significantly lower in the PICU group (adjusted OR: 0.45; 95%CI: 0.23-0.88). Death and unfavorable neurological outcomes occurred less often in the PICU group (adjusted OR: 0.29; 95%CI: 0.14-0.60). However, when limited to exogenous illness, PCPC scores (adjusted OR: 0.38; 95%CI: 0.07-1.99) or death/unfavorable outcomes (adjusted OR: 0.72; 95%CI: 0.08-6.34) did not differ between the groups. PCPC deterioration and overall sequelae/death rates were lower in PICUs for children with endogenous illnesses, although the outcomes of exogenous illness were similar between the 2 unit types. Further studies on the necessity of centralization are warranted.

DOI： 10.18926/AMO/60365

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.resuscitation.2020.05.007

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Authorship：Last author   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.envint.2020.105603

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Language：English   Publishing type：Research paper (scientific journal)  

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Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

The “national meeting effect” refers to worse patient outcomes when medical professionals attend academic meetings and hospitals have reduced staffing. The aim of this study was to examine differences in outcomes of patients with out-of-hospital cardiac arrest (OHCA) admitted during, before, and after meeting days according to meeting location and considering regional variation of outcomes, which has not been investigated in previous studies. Using data from a nationwide, prospective, population-based, observational study in Japan, we analyzed adult OHCA patients who underwent resuscitation attempts between 2011 and 2015. Favorable one-month neurological outcomes were compared among patients admitted during the relevant annual meeting dates of three national scientific societies, those admitted on identical days the week before, and those one week after the meeting dates. We developed a multivariate logistic regression model after adjusting for confounding factors, including meeting location and regional variation (better vs. worse outcome areas), using the “during meeting days” group as the reference. A total of 40,849 patients were included in the study, with 14,490, 13,518, and 12,841 patients hospitalized during, before, and after meeting days, respectively. The rates of favorable neurological outcomes during, before, and after meeting days was 1.7, 1.6, and 1.8%, respectively. After adjusting for covariates, favorable neurological outcomes did not differ among the three groups (adjusted OR (95% CI) of the before and after meeting dates groups was 1.03 (0.83–1.28) and 1.01 (0.81–1.26), respectively. The “national meeting effect” did not exist in OHCA patients in Japan, even after comparing data during, before, and after meeting dates and considering meeting location and regional variation.

DOI： 10.3390/ijerph16245130

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DOI： 10.2188/jea.JE20190089

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DOI： 10.1186/s12873-019-0282-x

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DOI： 10.1016/j.alit.2019.08.007

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DOI： 10.1080/19338244.2019.1631245

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Authorship：Lead author   Publishing type：Research paper (scientific journal)   Publisher：Ovid Technologies (Wolters Kluwer Health)  

DOI： 10.1097/ee9.0000000000000051

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Language：English   Publishing type：Research paper (scientific journal)  

OBJECTIVE: To examine the relationship between the catch-up growth of preterm, SGA children and their behavioral development. METHODS: We analyzed data from a large Japanese, nationwide, population-based, longitudinal survey that started in 2001. We restricted the study participants to preterm children with information on height at 2 years of age (n = 1667). Catch-up growth for SGA infants was defined as achieving a height at 2 years of age above -2.0 standard deviations for chronological age. We then used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) for the associations of SGA/catch-up status with neurobehavioral development both at 5.5 and 8 years of age, adjusting for potential infant- and parent-related confounding factors. RESULTS: Twenty-six percent of preterm SGA infants failed to catch up. SGA children without catch-up growth were more likely to be unable to listen without fidgeting (OR 2.51, 95% CI: 1.06-5.93) and unable to focus on one task (OR 2.66, 95% CI: 1.09-6.48) compared with non-SGA children at 5.5 years of age. Furthermore, SGA children without catch-up growth were at significant risk for inattention at 8 years of age. CONCLUSIONS: SGA infants with poor postnatal growth were at risk for attention problems throughout preschool-age to school-age among preterm infants. Early detection and intervention for attention problems among these infants is warranted.

DOI： 10.1016/j.braindev.2018.12.004

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Authorship：Lead author  

DOI： 10.2188/jea.JE20180126

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DOI： 10.3390/toxics7020022

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Authorship：Last author  

DOI： 10.1097/JOM.0000000000001554

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Language：English  

Sedatives are administered during extracorporeal membrane oxygenation (ECMO) therapy to ensure patient safety, reduce the metabolic rate and correct the oxygen supply-demand balance. However, the concentrations of sedatives can be decreased due to absorption into the circuit. This study examined factors affecting the absorption of a commonly used sedative, midazolam (MDZ). Using multiple ex vivo simulation models, three factors that may influence MDZ levels in the ECMO circuit were examined: polyvinyl chloride (PVC) tubing in the circuit, use of a membrane oxygenator in the circuit, and heparin coating of the circuit. We also assessed changes in drug concentration when MDZ was re-injected in a circuit. The MDZ level decreased to approximately 60% of the initial concentration in simulated circuits within the first 30 minutes. The strongest factor in this phenomenon was contact with the PVC tubing. Membrane oxygenator use tended to increase MDZ loss, whereas heparin circuit coating had no influence on MDZ absorption. Similar results were obtained when a second dose of MDZ was injected to the second-use circuits.

DOI： 10.18926/AMO/56645

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DOI： 10.1111/apa.14507

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Authorship：Lead author  

DOI： 10.1016/j.scitotenv.2018.11.194

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Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: The prevalence of multiple births has recently increased. However, the association between gestational age and long-term morbidity among twins remains unclear. AIMS: To examine the association of gestational age with child health and neurological development in early childhood among twins. STUDY DESIGN: Population-based longitudinal study. SUBJECTS: We included 947 children from 479 pairs of twins with information on gestational age. OUTCOME MEASURES: Hospitalization was used as an indicator of physical health, and responses to questions about age-appropriate behaviors were used as an indicator of neurobehavioral development. We conducted binomial log-linear regression analyses, controlling for both child and maternal variables in the model. We accounted for correlations within the pairs with generalized estimating equations. RESULTS: The early term group (i.e., 37 to 38 weeks of gestation) had a lower risk of poor child health and unfavorable neurodevelopment compared with the full term group (≥39 weeks of gestation) and preterm group (<37 weeks of gestation). Compared with the early term group, the adjusted risk ratios for hospitalization for all causes during the period from 7 to 18 months of age was 2.2 (95% confidence interval: 1.3-3.8) for very preterm children (<32 weeks of gestation), 1.1 (0.8-1.6) for moderately and late preterm children (32 to 36 weeks of gestation), and 1.8 (1.0-3.2) for full term children. CONCLUSION: We observed a U-shaped association of gestational age with child health and neurodevelopment. The early term group had the lowest risk of poor outcomes among twins.

DOI： 10.1016/j.earlhumdev.2018.11.005

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DOI： 10.1080/19338244.2018.1434474

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DOI： 10.1186/s40560-019-0392-2

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DOI： 10.1371/journal.pone.0207049

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DOI： 10.1080/19338244.2018.1535481

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.envint.2018.09.047

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Authorship：Last author   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

School absenteeism, particularly among junior high school students, has increased annually in Japan. This study demonstrates the relationship between subjective adjustment to school life and students’ absenteeism. Data were collected from 17,378 junior high school students in Japan. A longitudinal design was used for the study. Teachers were asked to distribute the Adaptation Scale for School Environments on Six Spheres (ASSESS) questionnaire to junior high school students and ask the students to fill out the questionnaire at the beginning of the 2014 academic year in April 2014, and the relationship between their subjective adjustment and absenteeism as measured by the total number of absent days during the 2014 academic year was evaluated by logistic regression and a survival analysis model. Low life satisfaction was associated with absences. The corresponding odds ratio (OR) was higher for seventh graders (OR 3.29, confidence interval (CI): 2.41–4.48, hazard ratio (HR) 5.57, CI: 3.51–8.84) than for students in other grades. Interpersonal relationships were significantly related to absenteeism for seventh and eighth graders in the group with scores less than 39 points. Lower adjustment to learning seemed to be related to absenteeism for seventh and eighth graders. For effective interventions, a well-designed study that uses detailed information regarding life-related covariates is necessary.

DOI： 10.3390/ijerph15102309

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Language：English   Publishing type：Research paper (scientific journal)  

OBJECTIVE: To elucidate whether the results of an intelligence test at preschool age are predictive of reading difficulty (RD) at school age among very low birth weight infants (VLBWI). METHODS: Subjects were 48 Japanese children whose birth weight was <1500 g and who regularly visited a follow-up clinic. All subjects completed the Wechsler Intelligence Scale for Children-III (WISC-III) during the last grade of kindergarten, and four reading tasks during the second to fourth grade of elementary school. All participants had a full-scale intelligence quotient score of 85 or higher. Subjects with a standard deviation reading time score greater than 2.0 in two or more tasks were considered to have RD. We evaluated the associations between each WISC-III score and RD using logistic regression analyses. Furthermore, we performed receiver operating characteristic (ROC) analysis to determine a cutoff WISC-III score predictive of RD. RESULTS: In the mutually-adjusted model, the adjusted odds ratio per 1 score increase of freedom from distractibility (FD) was 0.832 (95% confidence interval: 0.720-0.962). In the ROC analysis, an FD score of <95.5 was chosen as the cutoff value for predicting RD (sensitivity, 0.77; specificity, 0.74). CONCLUSION: The present study indicated that a lower FD score at preschool age, which was associated with deficits in verbal working memory and attention, is a risk factor for RD at school age among Japanese VLBWI. Further investigation is desired to clarify the cognitive deficits underlying RD in Japanese-speaking preterm children, and to establish appropriate interventions for these children.

DOI： 10.1016/j.braindev.2018.05.002

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Authorship：Lead author   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/19338244.2017.1343238

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Authorship：Lead author   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.ntt.2018.08.001

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DOI： 10.18926/AMO/56170

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Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1111/apa.14255

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.scitotenv.2018.02.334

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Authorship：Last author   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

In 1956 methylmercury poisoning, known as Minamata disease, was discovered among the inhabitants around the Shiranui Sea, Kyushu, Japan. Although about five hundred thousand people living in the area had supposedly been exposed to methylmercury, administrative agencies and research institutes had not performed any subsequent large scale, continuous health examination, so the actual extent of the negative health effects was not clearly documented. In 2009, we performed health surveys in order to examine residents in the polluted area and to research the extent of the polluted area and period of pollution. We analyzed data collected on 973 people (age = 62.3 ± 11.7) who had lived in the polluted area and had eaten the fish there and a control group, consisting of 142 persons (age = 62.0 ± 10.5), most of whom had not lived in the polluted area. Symptoms and neurological signs were statistically more prevalent in the four groups than in the control group and were more prevalent and severe in those who had eaten most fish. The patterns of positive findings of symptoms and neurological findings in the four groups were similar. Our data indicates that Minamata disease had spread outside of the central area and could still be observed recently, almost 50 years after the Chisso Company’s factory had halted the dumping of mercury polluted waste water back in 1968.

DOI： 10.3390/toxics6030039

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Authorship：Last author   Publishing type：Research paper (scientific journal)   Publisher：Paris Scholar Publishing  

DOI： 10.14485/hbpr.5.3.6

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Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1111/cea.13100

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Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/19338244.2017.1297762

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Publishing type：Research paper (scientific journal)   Publisher：BMJ  

<sec><title>Objective</title>We tested whether Cushing’s sign could predict severe traumatic brain injury (TBI) requiring immediate neurosurgical intervention (BI-NSI) in children after blunt trauma.

</sec><sec><title>Design</title>Retrospective cohort study using Japan Trauma Data Bank.

</sec><sec><title>Setting</title>Emergency and critical care centres in secondary and tertiary hospitals in Japan.

</sec><sec><title>Participants</title>Children between the ages of 2 and 15 years with Glasgow Coma Scale motor scores of 5 or less at presentation after blunt trauma from 2004 to 2015 were included. A total of 1480 paediatric patients were analysed.

</sec><sec><title>Primary outcome measures</title>Patients requiring neurosurgical intervention within 24 hours of hospital arrival and patients who died due to isolated severe TBI were defined as BI-NSI. The combination of systolic blood pressure (SBP) and heart rate (HR) on arrival, which were respectively divided into tertiles, and its correlation with BI-NSI were investigated using a multiple logistic regression model.

</sec><sec><title>Results</title>In the study cohort, 297 (20.1%) exhibited BI-NSI. After adjusting for sex, age category and with or without haemorrhage shock, groups with higher SBP and lower HR (SBP ≥135 mm Hg; HR ≤92 bpm) were significantly associated with BI-NSI (OR 2.84, 95% CI 1.68 to 4.80, P&lt;0.001) compared with the patients with normal vital signs. In age-specific analysis, hypertension and bradycardia were significantly associated with BI-NSI in a group of 7–10 and 11–15 years of age; however, no significant association was observed in a group of 2–6 years of age.

</sec><sec><title>Conclusions</title>Cushing’s sign after blunt trauma was significantly associated with BI-NSI in school-age children and young adolescents.

</sec>

DOI： 10.1136/bmjopen-2017-020781

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Authorship：Lead author   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.jpeds.2017.10.012

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.ctim.2017.11.011

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.jpeds.2017.09.002

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Authorship：Lead author   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.envpol.2017.09.060

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Publishing type：Research paper (scientific journal)   Publisher：Ovid Technologies (Wolters Kluwer Health)  

DOI： 10.1097/ede.0000000000000700

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Publishing type：Research paper (scientific journal)   Publisher：Oxford University Press (OUP)  

DOI： 10.1093/pubmed/fdw050

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY  

AimDespite increased interest in an obesity paradox (i.e. a survival advantage of being obese), evidence remains sparse in Japanese populations. We aimed to verify this phenomenon among community-dwelling older adults in Japan.
MethodsOlder adults aged 65-84 years randomly chosen from all 74 municipalities in Shizuoka Prefecture completed questionnaires including body mass index information. Participants were followed from 1999 to 2009. Following World Health Organization guidelines, participants were classified using an appropriate body mass index for Asian populations as follows: &lt;18.5 kg/m(2) (underweight), 18.5-23.0 kg/m(2) (normal weight), 23.0-27.5 kg/m(2) (overweight) and 27.5 kg/m(2) (obesity). We estimated hazard ratios and their 95% confidence intervals for all-cause mortality, controlling for sex, age, smoking status, alcohol consumption, physical activity, hypertension and diabetes mellitus.
ResultsCompared with normal-weight participants, overweight/obese participants tended to have lower hazard ratios; the multivariate hazard ratios (95% confidence interval) were 0.86 (0.62-1.19) for obesity, 0.83 (0.73-0.94) for overweight and 1.60 (1.40-1.82) for underweight. In subgroup analyses by sex and age, the hazard ratios tended to be lower among obese men, albeit not significantly; hazard ratios (95% confidence interval) were 0.56 (0.25-1.27) in men aged 65-74 years, and 0.78 (0.41-1.45) in men aged 75-84 years.
ConclusionsThe present study provides evidence of a conservative obesity paradox among older Japanese people, using the appropriate body mass index cut-off points for Asian populations. In particular, obese older men tend to have a lower risk of all-cause mortality. Geriatr Gerontol Int 2017; 17: 1257-1264.

DOI： 10.1111/ggi.12851

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Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1111/ped.13259

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Authorship：Lead author   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.envres.2017.02.002

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Publishing type：Research paper (scientific journal)   Publisher：Public Library of Science (PLoS)  

DOI： 10.1371/journal.pone.0172544

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Authorship：Lead author   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.envint.2016.11.016

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Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.braindev.2016.08.007

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD  

We examined the effects of maternal smoking location at home on hospitalization for respiratory tract infections among young children in Japan. We used the large nationwide population-based longitudinal survey and restricted study participants to children born after 37 gestational weeks and singleton births (n = 43,851). We evaluated the associations among children between the ages of 6 and 18months and between the ages of 18 and 30months, respectively. After adjusting for potential confounders, both maternal outdoor and indoor smoking were associated with the elevated risk. The adjusted odds ratios (95% confidence intervals) of maternal outdoor and indoor smoking (vs nonsmoking mothers) were 1.21 (1.01-1.44) and 1.18 (1.04-1.33), respectively, in children between the ages of 6 and 18months. We thus encourage a smoke-free home policy to protect children from second- and third-hand smoke exposure.

DOI： 10.1080/19338244.2016.1255582

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Background: Evidence linking air pollution with adverse health outcomes is accumulating. However, few studies have adopted a quasi-experimental design to evaluate whether decline in air pollution from regulatory action improves public health. We evaluated the effect of a diesel emission control ordinance introduced in 2003 on mortality rates in 23 wards of the Tokyo metropolitan area, Japan, from October 2000 to September 2012, taking into account change in mortality rates in a reference population (Osaka) with a introduction of such a regulation in 2009.
Methods: We obtained daily counts of all-cause and cause-specific mortality and concentrations of nitrogen dioxide (NO2) and particulate matter less than 2.5 mu m in diameter (PM2.5) during the study period. We employed interrupted time-series analysis to analyze the data.
Results: Decline in NO2 during the study period was similar in the two areas, while decline in PM2.5 and the improvement in age-standardized mortality rates were greater in Tokyo's 23 wards compared with Osaka. Even after adjusting for age-standardized mortality rates in Osaka, percent changes in mortality between the first 3-year interval (October 2000 to September 2003) and the last 3-year interval (October 2009 to September 2012) were -6.0% for all causes, -11% for cardiovascular disease, -10% for ischemic heart disease, -6.2% for cerebrovascular disease, -22% for pulmonary disease, and -4.9% for lung cancer. We did not observe a decline in mortality from other causes.
Conclusions: This quasi-experimental study in Tokyo suggests that emission control was associated with improvements in both air quality and health outcomes.

DOI： 10.1097/EDE.0000000000000546

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER/PLENUM PUBLISHERS  

Objective The effect of media use on child behavior has long been a concern. Although studies have shown robust cross-sectional relations between TV viewing and child behavior, longitudinal studies remain scarce. Methods We analyzed the Longitudinal Survey of Babies, conducted by Japan's Ministry of Health, Labour and Welfare since 2001. Among 53,575 families, 47,010 responded to the baseline survey; they were followed up every year for 8 years. Complete data were available for longitudinal analysis among 32,439 participants. Daily media use (TV viewing and video game-playing hours at ages 3, 4, and 5 years) was used as the main exposure. We employed an index of the children's self-regulatory behavior as the outcome variable. Odds ratios and 95 % confidence intervals (CIs) were estimated. Results Among boys, longer TV-viewing times at ages 4 and 5 were related to problematic self-regulatory behavior. Compared with boys who watched just 1-2 h of TV a day, those who watched it 4-5 h had a 1.79-fold greater risk (CI 1.22-2.64) of problematic self-regulatory behavior, according to parental report. Among girls, similar results were evident at ages 4 and 5 (e.g., adjusted odds ratios for 4-5 h daily viewing versus 1-2 h at age 4: 2.59; 95 % CI 1.59-4.22). Video games may have a protective effect on the risk of problematic self-regulatory behavior at ages 3 and 5. Conclusion Longer daily exposure to TV during early childhood (age 4-5) may be associated with subsequent problematic child self-regulatory behavior.

DOI： 10.1007/s10995-016-2031-z

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Language：English   Publisher：BMJ PUBLISHING GROUP  

DOI： 10.1136/jech-2015-207005

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER ACAD PEDIATRICS  

BACKGROUND AND OBJECTIVES: Kawasaki disease (KD) is the most common cause of childhood-acquired heart disease in developed countries. However, the etiology of KD is not known. Aberrant immune responses are considered to play key roles in disease initiation and breastfeeding can mature immune system in infants. We thus examined the association between breastfeeding and the development of KD.
METHODS: We used a nationwide population-based longitudinal survey ongoing since 2010 and restricted participants to a total of 37630 children who had data on their feeding during infancy. Infant feeding practice was queried at 6 to 7 months of age, and responses to questions about hospital admission for KD during the period from 6 to 30 months of age were used as outcome. We conducted logistic regression analyses controlling for child and maternal factors with formula feeding without colostrum as our reference group.
RESULTS: A total of 232 hospital admissions were observed. Children who were breastfed exclusively or partially were less likely to be hospitalized for KD compared with those who were formula fed without colostrum; odds ratios for hospitalization were 0.26 (95% confidence interval: 0.12-0.55) for exclusive breastfeeding and 0.27 (95% confidence interval: 0.13-0.55) for partial breastfeeding. Although the risk reduction was not statistically significant, feeding colostrum only also provided a protective effect.
CONCLUSIONS: We observed protective effects of breastfeeding on the development of KD during the period from 6 to 30 months of age in a nationwide, population-based, longitudinal survey in Japan, the country in which KD is most common.

DOI： 10.1542/peds.2015-3919

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Objective: To investigate neurological development in small for gestational age (SGA) infants, with a focus on full-term SGA infants.
Methods: We analyzed data from a large, Japanese, nationwide, population-based longitudinal survey started in 2001. We restricted the study to participants born before 42 weeks of gestation (n = 46,563). Parents were asked questions about motor and language development when the children were 2.5 years old, and about behavioral development at 5.5 years. We analyzed the relationships between SGA status and development by logistic regression. Odds ratios (ORs) and 95% confidence intervals (95% CI) were calculated for each outcome for full-term and preterm births, adjusting for potential infant- and parent-related confounding factors. We also calculated the population-attributable fractions to estimate the public impact of SGA births.
Results: SGA full-term children were more likely to demonstrate developmental delays at 2.5 years, e.g., being unable to walk alone (OR 3.0, 95% CI: 1.7, 5.3), compose a two-phrase sentence (OR 1.5, 95% CI: 1.2, 1.8), or use a spoon to eat (OR 1.5, 95% CI: 1.1, 1.9). SGA status also had some degree of negative impacts on behavioral problems at 5.5 years among term children, e.g., being unable to listen without fidgeting (OR 1.2, 95% CI: 1.1, 1.3), or remain patient (OR 1.1, 95% CI: 1.0, 1.2). The public health impacts were comparable between full-term and preterm SGA children at 2.5 years.
Conclusion: SGA is a risk factor for developmental delay, even in full-term infants, with non-negligible public health impacts. (c) 2016 published by Elsevier B.V. on behalf of The Japanese Society of Child Neurology.

DOI： 10.1016/j.braindev.2015.12.013

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Few studies have evaluated the effect of short-term exposure to particulate matter (PM) less than 2.5 mu m in diameter (PM2.5) or to coarse particles on infant mortality. We evaluated the association between short-term exposure to PM and infant mortality in Japan and assessed whether adverse health effects were observable at PM concentrations below Japanese air quality guidelines. We used a time-stratified, case-crossover design. The participants included 2086 infants who died in the 23 urbanized wards of the Tokyo Metropolitan Government between January 2002 and December 2013. We obtained measures of PM2.5 and suspended particulate matter (SPM; PM &lt; 7 mu m in diameter) from one general monitoring station. As a measure of coarse particles, we calculated PM7-2.5 by subtracting PM2.5 from SPM. We then used conditional logistic regression to analyze the data. Same-day PM2.5 was associated with increased risks of infant and postneonatal mortality, especially for mortality related to respiratory causes. For a 10 mu g/m(3) increase in PM2.5, the odds ratios were 1.06 (95% confidence interval: 1.01-1.12) for infant mortality and 1.10 (1.02-1.19) for postneonatal mortality. PM7-2.5 was also associated with an increased risk of postneonatal mortality, independent of PM2.5. Even when PM2.5 and SPM concentrations were below Japanese air quality guidelines, we observed adverse health effects. This study provides further evidence that acute exposure to PM2.5 and coarse particles (PM7-2.5) is associated with an increased risk of infant mortality. Further, rigorous evaluation of air quality guidelines for daily average PM2.5 and larger particles is needed. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.scitotenv.2016.01.211

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

Secondary sex ratio (i.e., male proportion at birth) is considered to function as a sentinel health indicator. Thus, examining this ratio spatially and temporally in regions with severe environmental exposure to compounds such as methylmercury may provide insight into the evolution of exposure.
We evaluated spatial and temporal distributions of the secondary sex ratio in Minamata, Japan, and neighboring areas, where severe methylmercury poisoning occurred in the 1950s and 1960s. We selected four areas exposed to methylmercury: Minamata, Ashikita, Goshonoura, and Izumi. After obtaining the number of live births, we conducted descriptive analyses by study area.
We observed a reduction in male births in the exposed areas. In particular, a decline in the sex ratio of the Minamata area, where the first patient was officially identified in 1956, was seen around 1955. The ratio during 1955-1959 around Minamata was 0.496 [95 % confidence interval (CI) 0.481-0.511]; the 95 % CI did not include the value of 0.515 (the secondary sex ratio of the entire Japanese population during the study period). Declines in this ratio were also observed in other exposed areas around 1960, when acetaldehyde production (the origin of methylmercury) reached its peak.
These analyses demonstrate that temporal and spatial distributions of the secondary sex ratio reflect the evolution of methylmercury exposure corresponding with the known history of Minamata disease.

DOI： 10.1007/s00420-015-1103-5

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BMJ PUBLISHING GROUP  

Objective To analyse the effect of different preterm birth categories on behavioural outcomes.
Design Prospective cohort design.
Settings The Japanese Longitudinal Survey of Babies in the 21st Century was used for the study.
Subjects Neonates born in 2001 in Japan (n= 34 163) and followed up at the age of 8 years. Post-term births were excluded and the sample was divided into four groups according to gestational age: &lt; 34 weeks, 34-36 weeks, 37-38 weeks and 39-41 weeks.
Outcome measures Seven behavioural outcomes were examined: three attention problems and four delinquent/aggressive behaviours.
Results Logistic regression was used to estimate adjusted ORs and 95% CIs for each outcome. Positive associations were found between preterm birth (&lt; 37 weeks) and adverse behavioural outcomes compared with full-term birth (39-41 weeks). For attention problems, the OR for 'inability to wait his/her turn' was increased by 1.72 (95% CI 1.22 to 2.43) for gestational age &lt; 34 weeks and by 1.28 (95% CI 1.03 to 1.59) for 34-36 weeks' gestation. For delinquent/aggressive behaviour, the OR for the outcome 'destroying books/toys' was increased by 1.46 (95% CI 1.07 to 1.99) for gestational age &lt; 34 weeks, while the outcome 'disturbance in public' was increased by 1.20 (95% CI 1.04 to 1.38) for 34-36 weeks' gestation.
Conclusions Children who are born &lt; 34 weeks, but also between 34 and 36 weeks, are at increased risk of behavioural problems related to attention and delinquent/aggressive behaviour when 8 years old.

DOI： 10.1136/archdischild-2015-309272

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：KOREAN ACAD MEDICAL SCIENCES  

Anthropometry measurements, such as height and weight, have recently been used to predict poorer birth outcomes. However, the relationship between maternal height and birth outcomes remains unclear. We examined the effect of shorter maternal height on low birth weight (LBW) among 17,150 pairs of Japanese mothers and newborns. Data for this analysis were collected from newborns who were delivered at a large hospital in Japan. Maternal height was the exposure variable, and LBW and admission to the neonatal intensive care unit were the outcome variables. Logistic regression models were used to estimate the associations. The shortest maternal height quartile (131.0-151.9 cm) was related to LBW (OR 1.91 [95% CI 1.64, 2.22]). The groups with the second (152.0-157.9 cm) and the third shortest maternal height quartiles (158.0-160.9 cm) were also related to LBW. A P trend with one quartile change also showed a significant relationship. The relationship between maternal height and NICU admission disappeared when the statistical model was adjusted for LBVV. A newborn's small size was one factor in the relationship between shorter maternal height and NICU admission. In developed countries, shorter mothers provide a useful prenatal target to anticipate and plan for LBW newborns and NICU admission.

DOI： 10.3346/jkms.2016.31.3.353

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Desert dust is considered to be potentially toxic and its toxicity may change during long-range transportation. In Asian countries, the health effects of desert dust in different locations are not well understood. We therefore evaluated the city-combined and city-specific effects of Asian dust events on all cause and cause-specific mortality in five populous cities in South Korea (Seoul) and Japan (Nagasaki, Matsue, Osaka and Tokyo). We obtained daily mean concentrations of Asian dust using light detection and ranging (lidar) between 2005 and 2011. We then evaluated city-specific and pooled associations of Asian dust with daily mortality for elderly residents (&gt;= 65 years old) using time-series analyses. Each 10 mu g/m(3) increase in the concentration of same-day (lag 0) or previous-day (lag 1) Asian dust was significantly associated with an elevated pooled risk of all-cause mortality (relative risk (RR): 1.003 [95% CI: 1.001-1.005] at lag 0 and 1.001 [95% CI: 1.000-1.003] at lag 1) and cerebrovascular disease (RR: 1.006 [95% CI: 1.000-1.011] at lag 1). This association was especially apparent in Seoul and western Japan (Nagasaki and Matsue). Conversely, no significant associations were observed in Tokyo, which is situated further from the origin of Asian dust and experiences low mean concentrations of Asian dust. Adverse health effects on all-cause and cerebrovascular disease mortality were observed in South Korea and Japan. However, the effects of Asian dust differed across the cities and adverse effects were more apparent in cities closer to Asian dust sources. (C) 2016 Published by Elsevier Ltd.

DOI： 10.1016/j.atmosenv.2015.12.063

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier Inc.  

During the summer of 1955, mass arsenic poisoning of bottle-fed infants occurred in the western part of Japan due to contaminated milk powder, and more than 100 died
some childhood victims were later found to suffer from neurological sequelae in adolescence. This unique incident enabled us to explore infancy as a critical period of arsenic exposure in regard to developmental neurotoxicity and its possible persistence through adulthood. The purpose of this work is to evaluate the association between developmental arsenic exposure and the neurological outcomes more than 50. years later. We conducted a retrospective cohort study during the period from April 2012 to February 2013 in two hospitals in Okayama Prefecture, Japan. The study sample consisted of 50 individuals: 27 known poisoning victims from Okayama Prefecture, and 23 non-exposed local controls of similar age. In addition to neurological examination, we adapted a battery of neurophysiological and neuropsychological tests to identify the types of brain functions affected by early-life arsenic exposure. While limited abnormalities were found in the neurophysiological tests, neuropsychological deficits were observed. Except for Finger tapping, all test scores in the exposed group - Vocabulary and Block Design from Wechsler Adults Intelligent Scale III, Design memory subtest from Wide Range Assessment of Memory and Learning 2, and Grooved pegboard test - were substantially below those obtained by the unexposed. The exposed group showed average performance at least 1.2 standard deviations below the average for the controls. Exposed participants performed less well than controls, even after exclusion of subjects with recognized disabilities or those with a high level of education. Adults who had suffered arsenic poisoning during infancy revealed neuropsychological dysfunctions, even among those subjects not recognized as having disabilities. Developmental neurotoxicity due to arsenic likely results in permanent changes in brain functions.

DOI： 10.1016/j.ntt.2015.12.001

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Background: Recent studies suggest that prenatal exposure to outdoor air pollution is associated with unfavorable neurodevelopment in children. We examined associations between prenatal exposure to traffic-related air pollution and child behavioral development milestone delays, using data from a nationwide population-based longitudinal survey in Japan, where the participants were recruited in 2001 and followed.
Methods: Particulate matter, nitrogen dioxide, and sulfur dioxide concentrations during the 9 months before birth were obtained at the municipality level and assigned to the participants who were born in the corresponding municipality. We analyzed data from singleton births with linked pollution data available (N = 33,911 at the maximum). We used responses to survey questions about age-appropriate behaviors at ages 2.5 and 5.5 years as indicators of behavioral development. We conducted multilevel logistic regression analysis, adjusting for individual and municipality-level variables.
Results: Air pollution exposure during gestation was positively associated with the risk of some developmental milestone delays at both ages. Specifically, air pollution was associated with verbal and fine motor development at age 2.5 years, and with behaviors related to inhibition and impulsivity at 5.5 years. In the fully-adjusted models, odds ratios following one-interquartile-range increase in nitrogen dioxide and suspended particulate matter were 1.24 (95% confidence interval: 1.07, 1.43) for inability to compose a two-phrase sentence at ages 2.5 and 1.10 (1.05, 1.16) for inability to express emotions at age 5.5 years, respectively.
Conclusions: Prenatal exposure to traffic-related air pollution was associated with behavioral development milestone delays of children in a nationally representative sample in Japan.

DOI： 10.1097/EDE.0000000000000361

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MARY ANN LIEBERT, INC  

Objectives: Ayurvedic oil-dripping treatment (Shirodhara) is often used for treating sleep problems. However, few properly designed studies have been conducted, and the quantitative effect of Shirodhara is unclear. This study sought to quantitatively evaluate the effect of sesame oil Shirodhara (SOS) against warm water Shirodhara (WWS) on improving sleep quality and quality of life (QOL) among persons reporting sleep problems. Methods: This randomized, single-blinded, crossover study recruited 20 participants. Each participant received seven 30-minute sessions within 2 weeks with either liquid. The washout period was at least 2 months. The Shirodhara procedure was conducted by a robotic oil-drip system. The outcomes were assessed by the Pittsburgh Sleep Quality Index (PSQI) for sleep quality, Epworth Sleepiness Scale (ESS) for daytime sleepiness, World Health Organization Quality of Life 26 (WHO-QOL26) for QOL, and a sleep monitor instrument for objective sleep measures. Changes between baseline and follow-up periods were compared between the two types of Shirodhara. Analysis was performed with generalized estimating equations. Results: Of 20 participants, 15 completed the study. SOS improved sleep quality, as measured by PSQI. The SOS score was 1.83 points lower (95% confidence interval [CI], -3.37 to -0.30) at 2-week follow-up and 1.73 points lower (95% CI, -3.84 to 0.38) than WWS at 6-week follow-up. Although marginally significant, SOS also improved QOL by 0.22 points at 2-week follow-up and 0.19 points at 6-week follow-up compared with WWS. After SOS, no beneficial effects were observed on daytime sleepiness or objective sleep measures. Conclusions: This pilot study demonstrated that SOS may be a safe potential treatment to improve sleep quality and QOL in persons with sleep problems.

DOI： 10.1089/acm.2015.0018

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Recent studies have reported adverse health effects of short-term exposure to coarse particles independent of particulate matter less than 2.5 mu m in diameter (PM2.5), but evidence in Asian countries is limited. We therefore evaluated associations between short-term exposure to particulate matter (PM) and mortality among older people in Tokyo, Japan. We used a time-stratified, case-crossover design. Study participants included 664,509 older people (&gt;= 65 years old) in the 23 urbanized wards of the Tokyo Metropolitan Government, who died between January 2002 and December 2013. We obtained PM2.5 and suspended particulate matter (SPM; PM &lt; 7 mu m in diameter) from one general monitoring station. We calculated PM7-2.5 by subtracting PM2.5 from SPM to account for coarse particles. We then used conditional logistic regression to estimate odds ratios (ORs) and 95 confidence intervals (CIs). Same-day PM2.5 and PM7-2.5 were independently associated with all-cause and cause-specificmortality related to cardiovascular and respiratory diseases; for example, both pollutants were positively associated with increased risk of all-cause mortality even after simultaneous adjustment for each pollutant: OR of 1.006 (95% CI: 1.003, 1.009) for PM2.5 and 1.016 (95% CI: 1.011, 1.022) for PM7-2.5. Even below concentrations stipulated by the Japanese air quality guidelines for PM2.5 and SPM (PM7), we observed adverse health effects. This study provides further evidence that acute exposure to PM2.5 and coarse particles is associated with increased risk of mortality among older people. Rigorous evaluation of air quality guidelines for daily average PM2.5 and larger particles should be continued. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.scitotenv.2015.10.113

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD  

In the 1950s, large-scale food poisoning caused by methylmercury was identified in Minamata, Japan. Although severe intrauterine exposure cases (ie, congenital Minamata disease patients) are well known, possible impacts of methylmercury exposure in utero among residents, which is likely at lower levels than in congenital Minamata disease patients, are rarely explored. In 2014, the authors examined neurological and neurocognitive functions among 18 exposed participants in Minamata, focusing on fine motor, visuospatial construction, and executive functions. More than half of the participants had some fine motor and coordination difficulties. In addition, several participants had lower performance for neurocognitive function tests (the Rey-Osterrieth Complex Figure test and Keio version of the Wisconsin card sorting test). These deficits imply diffuse brain damage. This study suggests possible neurological and neurocognitive impacts of prenatal exposure to methylmercury among exposed residents of Minamata.

DOI： 10.1080/19338244.2015.1080153

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD  

Severe methylmercury exposure occurred in Minamata, Japan. Only a limited number of epidemiological studies related to that exposure have been carried out. The evidence that methylmercury is cardiotoxic is very limited, and these studies provide only minimal support for that hypothesis. We therefore analyzed the data both from an investigation in Minamata and neighboring communities in 1971 and an investigation in 1974 in another area simultaneously. We included a total of 3,751 participants. We examined the association of residential area with neurological signs or blood pressure using logistic regression or multiple linear regression models, adjusting for sex and age. We found that the prevalence of neurological signs and symptoms was elevated in the Minamata area (high-exposure), followed by the Goshonoura area (medium-exposure). Moreover, blood pressure was elevated in residents of the Minamata area.

DOI： 10.1080/19338244.2015.1084261

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Authorship：Lead author   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/19338244.2014.904268

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER/PLENUM PUBLISHERS  

Whether or not the protective effects of breastfeeding last during or after a shift to a weaning diet is not clear. In the present study, we examined the effects of breastfeeding on hospitalization for respiratory tract infections and diarrhea in early childhood in Japan. Data were extracted from a nationwide longitudinal survey of Japanese children. We restricted the study participants to singleton children who were born after 37 gestational weeks and whose information on feeding practice during infancy were included (n = 43,367). We used logistic regression models to evaluate the associations of breastfeeding with hospitalization for the two diseases among young children (i.e., between ages 6 and 18 months, between ages 18 and 30 months, and between ages 30 and 42 months, respectively), adjusting for children's factors (sex, birth weight, childcare attendance and presence of siblings) and maternal factors (educational attainment and smoking status). Breastfeeding compared with infant formula was not associated with reduced risk of hospitalization for diarrhea during the periods we examined. Although breastfeeding was not associated with reduced risk of hospitalization for respiratory tract infections between ages 6 and 18 months, breastfeeding showed protective effects after that period: the adjusted odds ratios (95 % confidence intervals) of exclusive breastfeeding were 0.82 (0.66-1.01) between ages 18 and 30 months and 0.76 (0.58-0.99) between ages 30 and 42 months. Breastfeeding may have long-term protective effects on hospitalization for respiratory tract infections after infancy, but not for diarrhea.

DOI： 10.1007/s10995-015-1703-4

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CAMBRIDGE UNIV PRESS  

Objective: Whether or not breast-feeding is protective against asthma among children is still controversial. Therefore, we examined the effects of breast-feeding on hospitalization for asthma in early childhood.
Design: Secondary data analyses of a nationwide longitudinal survey of children in Japan ongoing since 2001, with results collected from 2001 to 2004. We used logistic regression models to evaluate the associations of breast-feeding with hospitalization for asthma in children between the ages of 6 and 42 months, adjusting for children's factors (sex, day-care attendance and presence of older siblings) and maternal factors (educational attainment and smoking habit).
Setting: All over Japan.
Subjects: Term singleton children with information on feeding practices during infancy (n 43 367).
Results: After adjusting for maternal factors and children's factors, exclusive breast-feeding at 6-7 months of age was associated with decreased risk of hospitalization for asthma in children. The adjusted odds ratio was 0.77 (95 % CI 0.56, 1.06). One-month longer duration of breast-feeding was associated with a 4 % decreased risk of hospitalization for asthma (OR= 0.96; 95 % CI 0.92, 0.99).
Conclusions: The protective effects of breast-feeding on hospitalization for asthma were observed in children between the ages of 6 and 42 months.

DOI： 10.1017/S1368980014002407

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Objective:
We aimed to evaluate the annual health impacts of particulate matter (PM) less than 10 mu m diameter (PM10) and less than 2.5-mu m diameter (PM2.5) in 27 cities in Southeast and East Asian countries (Japan, the Philippines, the Republic of Korea, Singapore, and Vietnam) for the year 2009 (n = 50,756,699).
Methods:
We estimated the number of cases attributable to long-term exposure. We used a scenario that reduced the annual mean values for PM10 and PM2.5 to 20 and 10 mu g/m(3), respectively.
Results:
A reduction in long-term exposure to PM10 and PM2.5 would have postponed 8% to 9% of all-cause mortality or about 37,000 deaths. One third of them were associated with cardiopulmonary mortality and one ninth of them were associated with lung cancer mortality.
Conclusions:
Current air pollution levels in Southeast and East Asian countries have a nonnegligible public health impact.

DOI： 10.1097/JOM.0000000000000485

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PUBLIC LIBRARY SCIENCE  

Background
Ambient ozone (O-3) concentration has been reported to be significantly associated with mortality. However, linearity of the relationships and the presence of a threshold has been controversial.
Objectives
The aim of the present study was to examine the concentration-response relationship and threshold of the association between ambient O-3 concentration and non-accidental mortality in 13 Japanese and Korean cities from 2000 to 2009.
Methods
We selected Japanese and Korean cities which have population of over 1 million. We constructed Poisson regression models adjusting daily mean temperature, daily mean PM10, humidity, time trend, season, year, day of the week, holidays and yearly population. The association between O-3 concentration and mortality was examined using linear, spline and linear-threshold models. The thresholds were estimated for each city, by constructing linear-threshold models. We also examined the city-combined association using a generalized additive mixed model.
Results
The mean O-3 concentration did not differ greatly between Korea and Japan, which were 26.2 ppb and 24.2 ppb, respectively. Seven out of 13 cities showed better fits for the spline model compared with the linear model, supporting a non-linear relationships between O-3 concentration and mortality. All of the 7 cities showed J or U shaped associations suggesting the existence of thresholds. The range of city-specific thresholds was from 11 to 34 ppb. The city-combined analysis also showed a non-linear association with a threshold around 30-40 ppb.
Conclusion
We have observed non-linear concentration-response relationship with thresholds between daily mean ambient O-3 concentration and daily number of non-accidental death in Japanese and Korean cities.

DOI： 10.1371/journal.pone.0129423

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OBJECTIVE: Behavioral problems are often associated with poor sleep habits in children. We investigated whether undesirable toddler-age sleep schedules may be related to school-age behavioral problems. METHODS: We analyzed the data of a nationwide longitudinal survey with available results from 2001 to 2011. The participants were 41,890 children. The predictors were waking time and bedtime at 2years of age, and the outcomes were assessed by determining the presence or absence of three attention problems and four aggressiveness problems at 8years of age. In logistic regression models with adjustments for confounding factors, we estimated odds ratios (ORs) and confidence intervals (CIs) for the association between toddler sleep schedules and behavior during primary-school age years. RESULTS: The outcomes of attention problems and aggressiveness problems were observed in 1.7% and 1.2% of children, respectively, at 8years of age. The OR of an irregular or late morning waking time at 2years of age with the outcome of aggressiveness problems was 1.52 (95% CI, 1.04-2.22) in comparison to an early waking time. The OR of an irregular or late bedtime with attention problems was 1.62 (95% CI, 1.12-2.36), and the OR of an irregular or late bedtime with aggressiveness problems was 1.81 (95% CI, 1.19-2.77) in comparison to an early bedtime. CONCLUSION: Poor toddler-age sleep schedules were found to predict behavioral problems during primary-school age years. Thus, good and regular sleep habits appear to be important for young children's healthy development.

DOI： 10.1016/j.braindev.2014.10.004

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

In 1968, rice oil contaminated with polychlorinated biphenyls and polychlorinated dibenzofurans caused a severe outbreak of food poisoning in Japan and was termed locally as "Yusho" (oil disease). In our previous study, we found that area-based standardized mortality ratios (SMRs) of some diseases were elevated shortly after the incident. This previous study, however, was unable to determine whether these elevated SMRs were a result of other area-specific factors. To overcome this limitation, we obtained mortality data from the 5 years before the incident and conducted an area-based study using vital statistics records dating from 1963 to 2002.
The population of Nagasaki Prefecture was set as the reference population for calculating SMRs. We also included data on cause-specific mortality attributable to cancer and expanded the population to encompass two severely exposed areas where contaminated rice oil was distributed (namely Tamanoura and Naru). We also calculated SMRs in the remainder of the Shimo-Goto region, excluding the exposed area, which was used as a comparison area.
Even after considering the time trends in mortality before the incident, mortality due to diabetes mellitus and heart disease, as well as all-cause mortality, was found to be elevated shortly afterward. Additionally, mortalities due to uterine cancer in Tamanoura and leukemia were also elevated at 30-34 and 10-59 years after the event in both exposed areas, respectively. SMRs for leukemia in Tamanoura were as high as 3.0 (95 % confidence interval 1.4-6.2) and 2.4 (1.2-4.8) 10-19 years later. In this period, SMRs for leukemia in the comparison area were not elevated.
Further epidemiological studies are needed regarding this rice-oil, "Yusho" outbreak, especially with regard to cancer and non-cancer mortality.

DOI： 10.1007/s00420-014-0966-1

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Exposure to air pollution is linked with an increased risk of preterm births. To provide further evidence on this relationship, we evaluated the association between proximity to major roads-as an index for air pollution exposure-and various obstetrical complications. Data were extracted from a database maintained by the perinatal hospital in Shizuoka, Japan. We restricted the analysis to mothers with singleton pregnancies of more than 22 weeks of gestation from 1997 to 2012 (n = 19,077). Using the geocoded residential information, each mother was assigned proximity to major roads. We then estimated multivariate adjusted odds ratios and their 95% confidence intervals (CIs) for the effects of proximity to major roads on various obstetrical complications (preeclampsia, gestational diabetes mellitus, placenta abruption, placenta previa, preterm premature rupture of membrane (pPROM), preterm labor, and preterm births). We found positive associations of proximity to major roads with preeclampsia and pPROM. Living within 200 m increased the odds of preeclampsia by 1.3 times (95% CI, 1.0-1.8) and pPROM by 1.6 times (95% CI, 1.1-2.2). Furthermore, living within 200 m increased the odds of preterm births by 1.4 fold (95% CI, 1.2-1.7). Exposure to traffic-related air pollution increased the risk of preeclampsia and pPROM in this study. We propose a mechanism responsible for the association between air pollution and preterm births. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.scitotenv.2014.11.077

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Introduction: Evidence has accumulated on the association between ambient air pollution and adverse birth outcomes. However, most of the previous studies were conducted in geographically distinct areas and suffer from lack of important potential covariates. We examined the effect of ambient air pollution on term low birth weight (LBW) using data from a nationwide population-based longitudinal survey in Japan that began in 2001.
Methods: We restricted participants to term singletons (n = 44,109). Air pollution concentrations during the 9 months before birth were obtained at the municipality level and were assigned to the participants who were born in the corresponding municipality. We conducted multilevel logistic regression analyses adjusting for individual and municipality-level variables.
Results: We found that air pollution exposure during pregnancy was positively associated with the risk of term LBW. In the fully adjusted models, odds ratios following one interquartile range increase in each pollutant were 1.09 (95% confidence interval: 1.00, 1.19) for suspended particulate matter (SPM), 1.11 (0.99, 1.26) for nitrogen dioxide (NO2), and 1.71 (1.18, 2.46) for sulfur dioxide (SO2). Specifically, effect estimates for SPM and NO2 exposure at the first trimester were higher than those at other trimesters, while SO2 was associated with the risk at all trimesters. Nonsmoking mothers were more susceptible to SPM and NO2 exposure compared with smoking mothers.
Conclusions: Ambient air pollution increases the risk of term LBW in amationally representative sample in Japan. (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.envint.2014.09.003

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BMJ PUBLISHING GROUP  

Objectives: We investigated the association between breastfeeding duration during the first half year of life and the risk of early childhood caries from the age of 30 to 66 months in Japan.
Design: Observational study of a longitudinal survey.
Setting: A secondary data analysis of the Japanese Longitudinal Survey of Babies in the 21st Century.
Participants: 43 383 infants at the age of 6 months.
Outcome measures: Early childhood caries-defined as a child's visit to a dentist for treatment of dental caries during the past 12 months-was ascertained from the caregiver from the age of 30 months in the survey. We estimated the risk of dental caries each year according to duration of breast feeding using logistic regression analyses. We controlled for a set of biological factors (birth weight, sex, parity and maternal age at delivery) and socioeconomic factors (maternal educational attainment and smoking status, marital status at delivery, family income and region of birth and residence).
Results: We found that infants who had been breast fed for at least 6 or 7 months, both exclusively and partially, were at elevated risk of dental caries at the age of 30 months compared with those who had been exclusively formula fed. Adjusted ORs were 1.78 (95% CI, (1.45 to 2.17)) for the exclusively breastfed group and 1.39 (1.14 to 1.70) for the partially breastfed group. However, the associations became attenuated through the follow-up period and were no longer statistically significant beyond the age of 42 months for the partially breastfed group and beyond the age of 54 months for the exclusively breastfed group.
Conclusions: We found an association between breast feeding for at least 6 or 7 months and elevated risk of dental caries at age 30 months. However, the association became attenuated as children grew older.

DOI： 10.1136/bmjopen-2014-006982

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Lippincott Williams and Wilkins  

Objective: To evaluate the direct health effects of Asian dust on ambulance calls and its role as an effect modifier on the effects of anthropogenic air pollution in Japan.
Methods: The subjects were 51,945 elderly residents who visited hospital emergency departments from 2006 to 2010. We evaluated the impact of Asian dust by time-series analyses and the excess risk from suspended particulate matter (SPM) stratified by Asian-dust exposure.
Results: Asian dust was associated with daily ambulance calls due to allcause, cardiovascular, and respiratory disease independently of SPM, for example, the relative risk per interquartile increase in Asian dust (3-day lag) was 1.021 (1.002 to 1.039) for cardiovascular disease. Furthermore, Asian dust modified the effects of SPM on cardiovascular and respiratory diseases.
Conclusions: Asian dust had adverse effects and modified the effect of SPM.

DOI： 10.1097/JOM.0000000000000334

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DOI： 10.1186/1476-069x-13-67

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Other Link： http://link.springer.com/article/10.1186/1476-069X-13-67/fulltext.html

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Lippincott Williams and Wilkins  

Objectives: We evaluated the association between short-term exposure to outdoor air pollution and out-of-hospital cardiac arrest in Japan.
Conclusions: Short-term exposure to outdoor air pollution was associated with increased risk of cardiac arrest.
Methods: We studied 558 residents of Okayama, Japan, who visited hospital emergency departments between January 2006 and December 2010 for out-of-hospital cardiac arrest using a time-stratified case-crossover design. We calculated city-representative average concentrations of different air pollutants and examined the association between air pollution and cardiac arrest.
Results: Exposure to air pollution was associated with an elevated risk of cardiac arrest
for example, odds ratios was 1.17 (95% confidence interval, 1.02 to 1.33) per interquartile-range increase in suspended particulate matter concentrations in the previous 48 to 72 hours. We also observed different susceptibilities to suspended particulate matter and ozone exposures by age category.

DOI： 10.1097/JOM.0000000000000274

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Authorship：Lead author   Language：English   Publishing type：Part of collection (book)   Publisher：Elsevier  

The history of Minamata disease is presented in chronological order (from the first outbreak to the current situation). The history of the disease provides us with invaluable lessons for future public health strategies. First, prompt countermeasures should be taken when a cause is identified and should not be postponed until an etiologic agent is identified. Second, lack of investigation obscures the features as well as the expansion of the disease and unnecessarily confuses the situation. Third, the womb is the environment. Finally, social circumstances can induce disease.

DOI： 10.1016/B978-0-12-386454-3.00038-5

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BACKGROUND: In industrializing countries, occupational safety and health have been affected by globalization. However, a lack of reliable data prevents evaluation of this situation. Therefore, we examined industrial distributions and risks of severe occupational injuries among workers in Thailand, which is one of the few industrializing countries that compiles nationwide data. METHODS: Data on workers who made claims for occupational injuries from 2007 to 2009 were extracted from the Workmen's Compensation Fund records in Thailand. Among 501,334 claimants, we evaluated the industrial distributions of severe occupational injuries (i.e., permanent disability and death). We then examined the associations between industry and those injuries, using proportionate ratios (PRs) between each industrial category and the overall distribution of occupational injuries. RESULTS: The number of workers in manufacturing making claims for severe occupational injuries was the largest among all industrial categories (319,114/501,334 injuries), although the total number of occupational injuries recently declined. Additionally, workers in manufacturing experienced severe occupational injuries more often compared with the overall distribution of occupational injuries. The PRs (95% confidence interval) for manufacturing were 1.17 (1.14-1.20) in men and 1.33 (1.27-1.38) in women. After adjusting for individual characteristics, the results did not substantially change. CONCLUSIONS: Manufacturing seems to have the largest burden of occupational injuries in industrializing countries like Thailand.

DOI： 10.1539/joh.13-0085-fs

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BACKGROUND AND PURPOSE-: Few studies have examined the effect of hourly changes in air pollution on cardiovascular disease morbidity. We evaluated the associations between hourly changes in air pollution and the risks of several types of cardiovascular disease. METHODS-: We used a time-stratified case-crossover design. Study participants were 10 949 residents of the city of Okayama, Japan, aged ?65 years who were taken to hospital emergency rooms between January 2006 and December 2010 for onset of cardiovascular disease. We calculated city representative hourly average concentrations of air pollutants from several monitoring stations and examined the associations between air pollution exposure before the case event, focusing mainly on suspended particulate matter, and disease onset. RESULTS-: Suspended particulate matter exposure 0 to &lt
6 hours before the case events was associated with risks of onset of cardiovascular and cerebrovascular disease
odds ratios after 1 interquartile range increase in suspended particulate matter exposure were 1.04 (95% confidence interval, 1.01-1.06) for cardiovascular disease and 1.04 (95% confidence interval, 1.00-1.08) for cerebrovascular disease. We observed an elevated risk of hemorrhagic as well as ischemic stroke, but the risk was slightly higher for hemorrhagic stroke, and this elevation was persistent. Women tended to have higher effect estimates. CONCLUSIONS-: This study provides further evidence that particulate matter exposure increases the risks of onset of cardiovascular and cerebrovascular disease (including hemorrhagic stroke) shortly after exposure. © 2014 American Heart Association, Inc.

DOI： 10.1161/STROKEAHA.114.005227

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Language：English   Publisher：Public Health Services, US Dept of Health and Human Services  

Background: Particulate matter (PM) in outdoor air pollution was recently designated a Group I carcinogen by the International Agency for Research on Cancer (IARC). This determination was based on the evidence regarding the relationship of PM2.5 and PM10 to lung cancer risk
however, the IARC evaluation did not include a quantitative summary of the evidence. Objective: Our goal was to provide a systematic review and quantitative summary of the evidence regarding the relationship between PM and lung cancer. Methods: We conducted meta-analyses of studies examining the relationship of exposure to PM2.5 and PM10 with lung cancer incidence and mortality. In total, 18 studies met our inclusion criteria and provided the information necessary to estimate the change in lung cancer risk per 10-μg/m3 increase in exposure to PM. We used random-effects analyses to allow between-study variability to contribute to meta-estimates. Results: The meta-relative risk for lung cancer associated with PM2.5 was 1.09 (95% CI: 1.04, 1.14). The meta-relative risk of lung cancer associated with PM10 was similar, but less precise: 1.08 (95% CI: 1.00, 1.17). Estimates were robust to restriction to studies that considered potential confounders, as well as subanalyses by exposure assessment method. Analyses by smoking status showed that lung cancer risk associated with PM2.5 was greatest for former smokers [1.44 (95% CI: 1.04, 1.22)], followed by never-smokers [1.18 (95% CI: 1.00, 1.39)], and then current smokers [1.06 (95% CI: 0.97, 1.15)]. In addition, meta-estimates for adenocarcinoma associated with PM2.5 and PM10 were 1.40 (95% CI: 1.07, 1.83) and 1.29 (95% CI: 1.02, 1.63), respectively. Conclusion: The results of these analyses, and the decision of the IARC Working Group to classify PM and outdoor air pollution as carcinogenic (Group 1), further justify efforts to reduce exposures to air pollutants that can arise from many sources.

DOI： 10.1289/ehp.1408092

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER PUBLIC HEALTH ASSOC INC  

Objectives. We examined the association between social cohesion and mortality in a sample of older adults in Japan.
Methods. Data were derived from a cohort study of elderly individuals (65-84 years) in Shizuoka Prefecture; 14 001 participants were enrolled at baseline (1999) and followed up in 2002, 2006, and 2009. Among the 11 092 participants for whom we had complete data, 1427 had died during follow-up. We examined the association between social cohesion (assessed at both the community and individual levels) and subsequent mortality after control for baseline and time-varying covariates. We used clustered proportional hazard regression models to estimate hazard ratios (HRs) and confidence intervals (CIs).
Results. After control for individual characteristics, individual perceptions of community cohesion were associated with a reduced risk of all-cause mortality (HR = 0.78; 95% CI = 0.73, 0.84) as well as mortality from cardiovascular disease (HR = 0.75; 95% CI = 0.67, 0.84), pulmonary disease (HR = 0.66; 95% CI = 0.58, 0.75), and all other causes (HR = 0.76; 95% CI = 0.66, 0.89). However, no statistically significant relationship was found between community cohesion and mortality risk.
Conclusions. Among the elderly in Japan, more positive individual perceptions of community cohesion are associated with reduced risks of all-cause and cause-specific mortality.

DOI： 10.2105/AJPH.2013.301311

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Objective To examine associations between the duration of gestation and health and development outcomes at 2.5 years and 5.5 years using a Japanese population-based longitudinal survey (n = 47 015).
Study design Hospitalization was used as an indicator of physical health, and responses to questions about age-appropriate behaviors were used as an indicator of behavioral development. We conducted logistic regression analyses controlling for a set of neonatal and family factors. We also estimated population-attributable fractions.
Results We observed a steady increase toward shorter duration of gestation in the risk of hospitalizations at age 2.5 years and 5.5 years and developmental delays at 2.5 years (P-linear (trend) &lt;.001 for all outcomes). We found associations only between extremely preterm birth and delayed behavioral development at age 5.5 years.
Conclusion There is a linear relationship between shorter duration of gestation and increased risk of later health and developmental problems. In line with Rose's "population paradox," the population-attributable risks for these problems are greater for moderately preterm infants compared with extremely preterm infants.

DOI： 10.1016/j.jpeds.2013.07.004

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A lower bodyweight may be associated with adverse birth outcomes, such as low birth weight and being small for a given gestational age. In Japan, the rate of low birth weight has been increasing over the last two decades, such that both low pre-pregnancy weight and inadequate weight gain during pregnancy are viewed as critical issues in terms of the reproductive health of Japanese women. The aim of our study was to evaluate the relationship between socioeconomic status (SES) and inadequate weight gain during pregnancy. A cross-sectional, hospital-based study using data from a large hospital in Hamamatsu city, Japan, from 1997 to 2010 was conducted. Among a total of 21,855 deliveries, 15,020 participants were analyzed. Odds ratios and confidence intervals were estimated using a logistic regression model. We defined maternal occupational status as follows: home-maker married to a salaried-spouse, home-maker married to a self-employed spouse, home-maker married to a professional, all other home-makers, office worker, professional, and all other occupations. In the high SES groups (home-makers married to self-employed spouse and professional spouse, as well as office workers and professional workers), we found an association with inadequate weight gain during pregnancy, especially among underweight women. There was no association between SES and inadequate weight gain among normal-weight and overweight women. Japanese women from higher socioeconomic backgrounds appear to be at greater risk for inadequate weight gain. This result may contribute to enhancing prenatal education on pregnancy-related weight gain in Japan.

DOI： 10.1007/s10995-012-1213-6

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OKAYAMA UNIV MED SCHOOL  

To clarify the relationship between attention deficit/hyperactivity disorder (AD/HD) and pervasive developmental disorders (PDD), we investigated the common features and differences of these disorders in neuropsychological profiles. The subjects were 4 groups of Japanese boys aged 6 to 15 years, categorized by diagnosis: AD/HD (n = 20), PDD with comorbid AD/HD (PDD+ : n = 16), PDD without comorbid AD/HD (PDD-: n = 8), and typically developing (n = 60). We evaluated executive function (EF) through verbal and visuospatial memory tasks, the Go/NoGo task, and the color-word matching Stroop task. We performed a categorical analysis to estimate the effects of the 3 disorders on EF and a dimensional analysis to estimate the effects of symptom scales on EF. We found that the AD/HD and PDD+ subjects had negative effects on verbal working memory and infra-individual response variability. The severity of these impairments was positively correlated with the inattentiveness score. The subjects with a PDD+ or PDD- diagnosis had poorer scores on interference control; the severity of this impairment was correlated with the PDD symptom score. Impairments in visuospatial working memory were detected in the AD/HD and PDD- groups but not in the PDD+ group. Impairments in inhibition of the pre-potent response were noted in all 3 categories. AD/HD and PDD share neuropsychological features, though each disorder has a specific impairment pattern. Our findings partially support the idea that AD/HD and PDD are on a spectrum.

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IMPORTANCE: Although it is suggested that breastfeeding is protective against obesity in children, the evidence remains inconclusive because of possible residual confounding by socioeconomic status or children's lifestyle factors. Most of the participants in the previous studies were children in Western developed countries, so studies in a different context are awaited. OBJECTIVE: To examine the associations of breastfeeding with overweight and obesity among schoolchildren in Japan, with adjustment for the potential confounders. DESIGN: Secondary data analyses of a nationwide longitudinal survey ongoing since 2001, with results collected from 2001 to 2009. SETTING: All over Japan. PARTICIPANTS: A total of 43,367 singleton children who were born after 37 gestational weeks and had information on their feeding during infancy. EXPOSURES: Five mutually exclusive infant feeding practice categories. MAIN OUTCOMES AND MEASURES: Underweight, normal weight (referent group), overweight, and obesity at 7 and 8 years of age defined by using international cutoff points of body mass index by sex and age. RESULTS: In multinomial logistic regression models with adjustment for children's factors (sex, television viewing time, and computer game playing time) and maternal factors (educational attainment, smoking status, and working status), exclusive breastfeeding at 6 to 7 months of age was associated with decreased risk of overweight and obesity compared with formula feeding. The adjusted odds ratios were 0.85 (95% CI, 0.69-1.05) and 0.55 (95% CI, 0.39-0.78) for overweight and obesity, respectively, at 7 years of age. Similar results were observed at 8 years of age. CONCLUSIONS AND RELEVANCE: Breastfeeding is associated with decreased risk of overweight and obesity among schoolchildren in Japan. Therefore, it would be better to encourage breastfeeding even in developed countries.

DOI： 10.1001/jamapediatrics.2013.2230

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Yusho disease, a polychlorinated biphenyl (PCB) and polychlorinated dibenzofuran (PCDF) mixed poisoning caused by contaminated rice oil, occurred in Japan in 1968. The evidence on reproductive outcome is limited. We therefore evaluated the regional impact of the exposure to the PCB and PCDF mixture on stillbirth rate and secondary sex ratio among the residents in two severely affected areas. We selected the regionally-affected towns of Tamanoura (n = 4390 in 1970) and Naru (n = 6569) in Nagasaki Prefecture, Japan, for study. We obtained data on stillbirths (spontaneous/artificial) and live-born births (total/male/female) from 1958 to 1994. For a decade and a half after the exposure, an increase in the rate of spontaneous stillbirths coincided with a decrease in the male sex ratio. Compared with the years 1958-1967, the ratios for spontaneous stillbirth rates were 2.16 (95% confidence interval: 1.58 to 2.97) for 1968-1977 and 1.80(95% confidence interval: 1.25 to 2.60) for 1978-1987. The sex ratio (male proportion) was 0.483 (95% confidence interval: 0.457 to 0.508) in the first 10 years after exposure. Exposure to a mixture of PCBs and PCDFs affected stillbirth and sex ratio for a decade and a half after the exposure. (C) 2013 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.envint.2013.05.002

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Prenatal exposure to methylmercury can cause both neurobehavioral deficits and neurophysiological changes. However, evidence of neurotoxic effects within the visual nervous system is inconsistent, possibly due to incomplete statistical adjustment for beneficial nutritional factors. We evaluated the effect of prenatal methylmercury exposure on visual evoked potential (VEP) latencies in Faroese children with elevated prenatal methylmercury exposure. A cohort of 182 singleton term births was assembled in the Faroe Islands during 1994-1995. At age 7 years, VEP tracings were obtained from 139 cohort subjects after exclusion of subjects with abnormal vision conditions. We used multiple regression analysis to evaluate the association of mercury concentrations in cord blood and maternal hair at parturition with VEP latencies after adjustment for potential confounders that included the cord-serum phospholipid concentration of n-3 polyunsaturated fatty acids (PUFAs) and the duration of breastfeeding. Unadjusted correlations between mercury exposure and VEP latencies were equivocal. Multiple regression models showed that increased mercury concentrations, especially in maternal hair, were associated with delayed latencies for VEP peak N145. After covariate adjustment, a delay of 2.22. ms (p= 0.02) was seen for each doubling of the mercury concentration in maternal hair. In agreement with neuropsychological findings, the present study suggests that prenatal methylmercury exposure may have an adverse effect on VEP findings despite the absence of clinical toxicity to the visual system. However, this association was apparent only after adjustment for n-3 PUFA status. © 2013.

DOI： 10.1016/j.neuro.2013.03.009

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Objective: Evidence linking short-term exposure to outdoor air pollution with hemorrhagic stroke is inconclusive. Methods: We evaluated the effects of suspended particulate matter (SPM) on cardiovascular disease mortality, focusing on types of stroke, from March 2005 to December 2010, in five selected prefectures in western Japan. A multicity time-series analysis was used, and Asian dust was adjusted in the models. Results: Even after adjusting for Asian dust, the same-day SPM was positively associated with several types of stroke mortality. Following a 10-mu g/m(3) increase in SPM, rate ratios were 1.014 (90% confidence interval [CI]: 1.002 to 1.026) for stroke, 1.030 (90% CI: 1.004 to 1.056) for intracerebral hemorrhage, and 1.016 (90% CI: 1.003 to 1.030) for ischemic stroke mortality. Conclusions: Short-term exposure to outdoor air pollution may increase the risks of hemorrhagic stroke as well as ischemic stroke mortality.

DOI： 10.1097/JOM.0b013e3182973092

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Background Barker's fetal programming hypothesis suggests that disproportionate size at birth may have a lifelong impact on one's health. However, the literature on birth length is considerably more sparse compared with birthweight. We, therefore, examined the relationship between birth length and hospitalisation early in life among Japanese children. Methods We used the nationwide Longitudinal Survey of Babies in 21st Century and restricted the study subjects to full-term singleton babies (n=44057). We estimated the effects of birth length and birthweight on the risk of hospitalisation using log linear regression models. We controlled for a set of neonatal and maternal factors. Results Birth length was associated with the chance of hospitalisation due to all causes between 6 and 18 months of age. In addition, the association was stronger than that with birthweight. Adjusted risk ratios showed that the relationship between birth length and hospitalisation was U-shaped: 1.16 [95% confidence intervals, 1.08, 1.25] at 30-48cm, 1 [Reference] at 49cm, 1.13 [1.04, 1.22] at 50cm, and 1.11 [1.02, 1.20] at 51-60cm. Short babies with low or high weight, as well as long babies with low weight, seem to be at increased risk of hospitalisation. Conclusions We found a U-shaped relationship between birth length and risk of hospitalisation due to all causes during the period from 6 to 18 months.

DOI： 10.1111/ppe.12062

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Objectives: Controversy remains over whether declines in male births reported after population stressors result from either or both reduced conception of males or increased selection in utero against male fetuses. We use monthly birth cohorts to determine if Japanese male births following the Great East Japan Earthquake of 2011 fell below levels expected from female births and from history (i.e., autocorrelation) among cohorts exposed to the Earthquake at or after conception. Methods: We apply interrupted time-series methods to 69 months (i.e., April, 2006 through December, 2011) of birth data from the most and least affected prefectures as well as from the remainder of Japan. We estimate expected male births from female births and from autocorrelation. Results: Findings varied by distance from the greatest damage but suggest sensitive periods both early and late in gestation when population stressors may induce selection against males in utero. Support for reduced conception of males appeared only in the prefectures most damaged by the Earthquake. Conclusions: Results align with the claim that natural selection has conserved mechanisms that reduce the odds of a male live birth during stressful times by reducing the conception of males and by increasing the rate of spontaneous abortion among male fetuses. Am. J. Hum. Biol. 25:555-559, 2013. © 2013 Wiley Periodicals, Inc.

DOI： 10.1002/ajhb.22414

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DOI： 10.1016/j.puhe.2012.12.011

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：BIOMED CENTRAL LTD  

Background: Exposure to air pollution has been demonstrated to increase the risk of preterm birth and low birth weight (LBW). Although evidence has accumulated on characteristics associated with increased risk of air pollution-related health effects, most studies have been conducted in the adult population and evidence on reproductive outcomes is limited. We examined whether socio-economic position (SEP) and parental characteristics (parental behavior and co-morbidity) modified the relationship between air pollution and adverse birth outcomes.
Methods: Data were extracted from a perinatal hospital database based in Shizuoka, Japan. We restricted the analysis to mothers who delivered live-born single births from January 1997 to December 2010 (n = 16,615). Each birth was assigned proximity to major roads. Multivariate adjusted odds ratios (ORs) and their 95% confidence intervals (CIs) were estimated for the outcomes of preterm birth and term LBW. We stratified subjects by individual/area-level SEP and parental characteristics. We then measured interactions on the additive scale between the respective factors and exposure.
Results: Lower SEP at both individual and area levels was associated with the increased occurrence of adverse birth outcomes. Living within 200 m from a major road increased the risk of preterm birth by 1.5 times (95% CI: 1.3-1.9) and LBW by 1.2 times (95% CI: 0.9-1.6). Mothers with lower individual SEP defined by household occupation experienced higher ORs for term LBW (OR = 3.1, 95% CI: 1.2-8.2) compared with those with higher individual SEP. In contrast, mothers who lived in the highest area-level SEP region (i.e., affluent areas) showed slightly higher point estimates compared with those who lived in middle or poor areas. In addition, maternal diabetic and hypertensive status modified the association between proximity and preterm birth, while maternal smoking status modified the association between proximity and term LBW.
Conclusions: The present study demonstrated that air pollution is an independent risk factor for adverse birth outcomes. Mothers with lower individual SEP and mothers living in higher SEP region may be susceptible to the adverse effect of air pollution. Maternal diabetic, hypertensive, and smoking status may also increase susceptibility to this air pollution-related health effect.

DOI： 10.1186/1476-069X-12-34

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：HUMAN KINETICS PUBL INC  

Few epidemiological studies have examined the potential protective effects of physical activity on insomnia. The authors thus evaluated the association between physical activity and insomnia in a large population-based study in Shizuoka, Japan. Individual data were obtained from participants in an ongoing cohort study. A total of 14,001 older residents who completed questionnaires were followed for 3 yr. Of these, 10,211 and 3,697 participants were eligible for the cross-sectional and longitudinal analyses, respectively. The authors obtained information about the frequency of physical activity and insomnia. Then, the adjusted odds ratios and 95% confidence intervals between physical activity and insomnia were estimated. Habitual physical activity was related to lower prevalence of insomnia. Frequent physical activity also reduced the incidence of insomnia, especially difficulty maintaining sleep. For elderly people with sufficient mobility and no preexisting disease, high-frequency physical activity (e.g., 5 or more days/wk) may help reduce insomnia.

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD  

Large-scale food poisoning caused by methylmercury was identified in Minamata, Japan, in the 1950s (Minamata disease). Although the diagnostic criteria for the disease remain current, few studies have been carried out to assess the diagnostic accuracy of the criteria. From a 1971 population-based investigation, data from 2 villages were selected: Minamata (high-exposure area; n = 779) and Ariake (low-exposure area; n = 755). The authors examined the prevalence of neurologic signs characteristic of methylmercury poisoning and the validity of the criteria. A substantial number of residents in the exposed area exhibited neurologic signs even after excluding officially certified patients. Using paresthesia of the extremities as the gold standard of diagnosis, the criteria had a sensitivity of 66%. The current diagnostic criteria as well as the official certification system substantially underestimate the incidence of Minamata disease.

DOI： 10.1080/19338244.2011.627894

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

A number of studies have linked exposure to long-term outdoor air pollution with cardiopulmonary disease; however, the evidence for stroke is limited. Furthermore, evidence with the risk for lung cancer (LC) is still inconsistent. We, therefore, evaluated the association between long-term exposure to traffic-related air pollution and cause-specific mortality. Individual data were extracted from participants of an ongoing cohort study in Shizuoka, Japan. A total of 14,001 elderly residents completed questionnaires and were followed from December 1999 to January 2009. Annual individual nitrogen dioxide (NO2) exposure data, as an index for traffic-related exposure, were modeled using a Land Use Regression model and assigned to the participants. We then estimated the adjusted hazard ratios (HRs) and their confidence intervals (CIs) associated with a 10 mu g/m(3) elevation in NO2 for all-cause or cause-specific mortality using time-varying Cox proportional hazards models. We found positive associations of NO2 levels with all-cause (HR = 1.12, 95% CI: 1.07-1.18), cardiopulmonary disease (HR = 1.22, 95% CI: 1.15-1.30), and LC mortality (HR = 1.20, 95% CI: 1.03-1.40). Among cardiopulmonary disease mortality, not only the risk for ischemic heart disease (HR = 1.27,95% CI: 1.11-1.47) but also the risks for stroke were elevated: intracerebral hemorrhage (HR = 1.28,95% CI: 1.05-1.57) and ischemic stroke (HR = 1.20,95% CI: 1.04-1.39). The present study supports the existing evidence that long-term exposure to traffic-related air pollution increases the risk of cardiopulmonary as well as LC mortality, and provides additional evidence for adverse effects on intracerebral hemorrhage as well as ischemic stroke. (C) 2012 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.scitotenv.2012.10.088

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BMJ PUBLISHING GROUP  

Objective Desert dust, which is included in course particles, is considered to have potential toxicity. The effect modification of desert dust on associations between anthropogenic air pollution and mortality has been evaluated. However, the independent effects of Asian dust are less clear. Thus, we evaluated the effects of Asian dust on mortality independent of particulate matter (PM) in western Japan.
Methods We obtained daily mean concentrations of Asian dust using Light Detection and Ranging measurements and suspended particulate matter (SPM) concentrations (approximately PM8) during March 2005 to December 2010. We then evaluated city-specific associations of Asian dust and SPM with daily mortality using a time-series analysis targeting 1 379 052 people aged 65 or above living in 47 cities. The city-specific results were then combined with a Bayesian-hierarchical model.
Results Asian dust did not modify the effects of SPM on mortality. Meanwhile, Asian dust was adversely associated with mortality independent of SPM. The excess risk following a 10 mu/m(3) increase in mean of the current to the previous 2 days Asian dust concentration was 0.6% (95% CI 0.1 to 1.1) for heart disease, 0.8% (95% CI 0.1 to 1.6) for ischaemic heart disease, 2.1% (95% CI 0.3 to 3.9) for arrhythmia and 0.5% (95% CI 0.2 to 0.8) for pneumonia mortality. Furthermore, the effects of Asian dust were stronger in northern areas close to the Eurasian continent (source of Asian dust).
Conclusions Asian dust had adverse effects on circulatory and respiratory mortality independent of PM.

DOI： 10.1136/oemed-2012-100797

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：BIOMED CENTRAL LTD  

Background: The proportions of preterm birth (PTB, ie., delivered before 37 gestational weeks) and low birth weight (LBW, ie., birth weight less than 2500 g at delivery) have been rising in developed countries. We sought to examine the factors contributing to the rise in Japan, with particular focus on the effects of obstetric interventions.
Methods: We used a database maintained by one large regional hospital in Shizuoka, Japan. We restricted the analysis to mothers who delivered live singleton births from 1997 to 2010 (n = 19,221). We assessed the temporal trends in PTB and LBW, then divided the study period into four intervals and compared the proportions of PTB and LBW. We also compared the newborns' outcomes between the intervals.
Results: PTB, in particular medically indicated PTB, increased considerably. The increase was largely explained by changes in caesarean sections. The neonatal outcomes did not worsen, and instead the Apgar scores and proportions requiring neonatal intensive care unit (NICU) admission improved. In particular, the risks of NICU admission in the interval from 2007 to 2010 were decreased among all births [odds ratio (OR): 0.84; 95% confidence interval (CI): 0.75, 0.95] and medically indicated births (OR: 0.44; 95% CI: 0.29, 0.68) compared with the interval from 1997 to 2000.
Conclusions: Despite the increases in PTB as well as LBW, the present study suggests benefits of obstetric interventions. Rather than simple categorization of PTB or LBW, indicators such as perinatal mortality or other outcomes may be more appropriate for evaluation of perinatal health in developed countries.

DOI： 10.1186/1471-2393-12-162

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS  

Objective: To examine the relationship between frequency of antenatal care visits, as a whole and in each trimester, and neonatal mortality in Indonesia. Subjects: 13 055 single births from the fifth Indonesia Demographic Health Survey in 2006-07. Methods: Estimate adjusted odds ratios (ORs) and their 95% confidence intervals (95% CIs). Results: Pregnant women who had more antenatal care visits experienced a lower risk of neonatal mortality and more benefit in the last trimester: the ORs against the 0-1 visit group, were 0.76 (95% CI 0.45-1.29) for 2 visits group, 0.54 (95% CI 0.33-0.87) for 3 visits group and 0.31 (95% CI 0.17-0.57) for 4 visits group, respectively. Individual ORs as a whole period were not significant, but ORs declined markedly at 7 visits or more. Conclusion: The results may provide a valuable recommendation for the care of pregnant women in Indonesia.

DOI： 10.1093/tropej/fmr067

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN SOC OCCUPATIONAL HEALTH  

Does Open-air Exposure to Volatile Organic Compounds near a Plastic Recycling Factory Cause Health Effects?: Takashi YORIFUJI, et al. Department of Human Ecology, Okayama University Graduate School of Environmental Sciences-Objectives: After a plastic reprocessing factory began to operate in August 2004, the residents around the factory in Neyagawa, Osaka, Japan, began to complain of symptoms. Therefore, we conducted an exposure assessment and a population-based epidemiological study in 2006. Methods: To assess exposure, volatile organic compounds (VOCs) and total VOCs were measured at two locations in the vicinity of the factory. In the population-based study, a total of 3,950 residents were targeted. A self-administered questionnaire was used to collect information about subjects' mucocutaneous or respiratory symptoms. Using logistic regression models, we compared the prevalence of symptoms in July 2006 by employing the farthest area from the factory as a reference, and prevalence odds ratios (PORs) and their 95% confidence intervals (Cis) were estimated. Results: The concentration of total VOCs was higher in the vicinity of the factory. The prevalence of mucocutaneous and respiratory symptoms was the highest among the residents in the closest area to the factory. Some symptoms were significantly increased among the residents within 500 m of the factory compared with residents of an area 2800 m from the factory: e.g., sore throat (POR=3.2, 95% CI: 1.3-8.0), eye itch (POR=3.0, 95% CI: 1.5-6.0), eye discharge (POR=6.0, 95% CI: 2.3-15.9), eczema (POR=3.0, 95% CI: 1.1-7.9) and sputum (POR=2.4, 95% CI: 1.1-5.1). Conclusions: Despite of the limitations of this study, these results imply a possible association of open-air VOCs with mucocutaneous and respiratory symptoms. Because this kind of plasticre cycling factory only recently came into operation, more attention should be paid to the operation of plastic recycling factories in the environment. (J Occup Health 2012; 54: 79-87)

DOI： 10.1539/joh.11-0202-oa

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Recent studies suggest potential adverse effects of methylmercury exposure on myocardial infarction and hypertension, although the evidence is still limited. We thus evaluated this association using age-standardized mortality ratios (ASMRs) in Minamata, where severe methylmercury poisoning had occurred. We obtained mortality data from annual vital statistics and demographic statistics from census. We then compared mortality of atherosclerotic heart disease including degenerative heart disease and hypertension in Minamatacity with those in Kumamoto Prefecture, which includes Minamata city, as a control. We estimated ASMRs and 95% confidence intervals (CIs) during the period from 1953 to 1970. ASMRs of atherosclerotic heart disease were continuously decreased during the period from 1953 to 1967. In contrast, the ASMR of hypertension was significantly elevated during the period from 1963 to 1967 (SMR= 1.38, CI; 1.06-1.80); but they decreased later. Although dilution is present in this ecological study, our study supports the notion that methylmercury exposure induces hypertension. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.scitotenv.2011.11.076

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Language：English   Publishing type：Part of collection (book)   Publisher：Springer US  

Methylmercury neurotoxicity has been gradually recorded over several decades. Designs of recent epidemiologic studies have improved to focus their assessments in developmental neurotoxicity. The developing brain, due to rapid physiologic changes and a protective system under development, is particularly vulnerable to the exposure to environmental insults. This chapter aims to systematically review and discuss the state-of-the-art epidemiological studies published up to the present days. We also describe and discuss some of the methodological problems. For example, the uncertainties (confounding) derived from a situation in which an association between an exposure and an outcome is distorted because it is mixed with the effect of a confounding variable. A majority of the studies have demonstrated that methylmercury exposure is neurotoxic to adults and children, but stronger adverse effects would result if negative confounding derived from the nutritional factors of seafood is taken into consideration in the data analyses. The EU and US decision to take preventive measures occurred at a substantial delay following the discovery of these neurotoxic effects.

DOI： 10.1007/978-1-4614-2383-6_2

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Exposure to air pollution has been demonstrated to increase the risk of preterm birth and low birth weight. We examined whether proximity to major roads (as a marker of exposure to air pollution) is associated with increased placenta/birth weight ratio (as a biomarker of the placental transport function). Data on parental characteristics and birth outcomes were extracted from the database maintained by a major hospital in Shizuoka Prefecture, Japan. We restricted the analysis to mothers who delivered liveborn single births from 1997 to 2008 (n = 14,189). Using geocoded residential information, each birth was classified according to proximity to major roads. We examined the association between proximity to major roads and the placenta/birth weight ratio, using multiple linear regression. Proximity to major roads was associated with higher placenta/birth weight ratio. After adjusting for potential confounders, living within 200 m of a major road increased the ratio by 0.48% (95% CI = 0.15 to 0,80). In addition, proximity to major roads was associated with lower placenta weight and birth weight. These observed associations were stronger among participants living closer to major roads. Exposure to traffic-related air pollution is associated with higher placenta/birth weight ratio. Impaired placental oxygen and nutrient transport function might be a mechanism for explaining the observed association between air pollution and low birth weight as well as preterm birth. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.scitotenv.2011.11.001

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The functioning of an arteriovenous fistula (AVF) used for vascular access during hemodialysis has been assessed mainly by dilution methods. Although these techniques indicate the immediate recircula-tion rate, the results obtained may notcorrelate with Kt/V. In contrast, the clearance gap (CL-Gap) method provides the total recirculation rate per dialysis session and correlates well with Kt/V. We assessed the correlation between Kt/V and CL-Gap as well as the change in radial artery (RA) blood flow speed in the fistula before percutaneous transluminal angioplasty (PTA) in 45 patients undergoing continuous hemodialysis. The dialysis dose during the determination of CL-Gap was 1.2 to 1.4 Kt/V. Patients with a 10% elevation or more than a 10% relative increase in CL-Gap underwent PTA (n = 45), and the values obtained for Kt/V and CL-Gap before PTA were compared with those obtained immediately afterward. The mean RA blood flow speed improved significantly (from52.9 to 97.5 cm/ sec) after PTA, as did Kt/V (1.07 to 1.30) and CL-Gap (14.1% to 0.2%). A significant correlation between these differences was apparent (r = 0.436 and/&gt
= 0.003). These findings suggest that calculating CL-Gap may be useful for determining when PTA is required and for assessing the effectiveness of PTA, toward obtaining better dialysis. © 2012 by Okayama University Medical School.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：HINDAWI PUBLISHING CORPORATION  

Background. Large-scale poisonings caused by methyl mercury (MeHg) have occurred in Japan (Minamata in the 1950s and Niigata in the 1960s) and Iraq (in the 1970s). The current WHO neurological risk standard for adult exposure (hair level: 50 mu g/g) was based partly on evidence from Niigata which did not consider any cases who were diagnosed later and/or exposed to low level of MeHg (hair mercury level less than 50 mu g/g). Methods. Early in the Niigata epidemic in June 1965 there were two extensive surveys. From these two surveys, we examined 103 adults with hair mercury measurement who consulted two medical institutions. We compared the prevalence and the distribution of neurological signs related to MeHg poisoning between exposure categories. Result. We found 48 subjects with neurological signs related to MeHg poisoning who had hair mercury concentration less than 50 mu g/g. Among the neurological signs, sensory disturbance of the bilateral distal extremities was observed more frequently, followed by disequilibrium, hearing impairment, and ataxia, in groups with hair MeHg concentration both below 50 mu g/g and over 50 mu g/g. Conclusion. The present study suggests the possibility that exposure to MeHg at levels below the current WHO limits could cause neurologic signs, in particular, sensory disturbance.

DOI： 10.1155/2012/635075

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Yorifuji T, Tanihara S, Inoue S, Takao S, Kawachi I. The role of medicine in the decline of post-War infant mortality in Japan. Paediatric and Perinatal Epidemiology 2011; 25: 601-608.
The infant mortality rate (IMR) in Japan declined dramatically in the immediate post-War period (1947-60) in Japan. We compared the time trends in Growth Domestic Product (GDP) in Japan against declines in IMR. We then conducted a prefecture-level ecological analysis of the rate of decline in IMR and post-neonatal mortality from 1947 to 1960, focusing on variations in medical resources and public health strategies. IMR in Japan started to decline after World War II, even before the era of rapid economic growth and the introduction of a universal health insurance system in the 1960s. The mortality rates per 1000 infants in 2009 were 2.38 for IMR, 1.17 for neonatal mortality and 1.21 for post-neonatal mortality. The rate of decline in IMR and preventable IMR (PIMR) during the post-War period was strongly correlated with prefectural variations in medical resources (per capita physicians, nurses, and proportion of in-hospital births). The correlation coefficients comparing the number of physicians in 1955 with the declines in IMR and PIMR from 1947 to 1960 were 0.46 [95% confidence interval (CI) 0.19, 0.66] and 0.39 [95% CI 0.11, 0.61], respectively. By contrast, indicators of public health strategies were not associated with IMR decline. The IMR in Japan has been decreasing and seems to be entering a new era characterised by lower neonatal compared with post-neonatal mortality. Furthermore, the post-War history of Japan illustrates that improvement in infant mortality is attributable to the influence of medical care, even in the absence of rapid economic development.

DOI： 10.1111/j.1365-3016.2011.01216.x

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Evidence linking air pollution with adverse cardiopulmonary outcomes is accumulating. However, few studies have been conducted to evaluate whether vehicle emission control improves public health. We thus evaluated the effect of a diesel emission control law on mortality rates in 23 wards of Tokyo metropolitan area, Japan. We obtained daily counts of mortality and concentrations of nitrogen dioxide (NO(2)) and particulate matter less than 2.5 mu m in diameter (PM(2.5)) from April 2003 to December 2008. Time-series and interrupted time-series analysis were employed to analyze the data in two periods: prior to the introduction of tighter restrictions (April 2003 to March 2006) and after the enforcement (April 2006 to December 2008). Concentrations of air pollutants gradually decreased during the study period: from 36.3 ppb (NO(2)) and 22.8 mu g/m(3) (PM(2.5)) to 32.1 ppb and 20.3 mu g/m(3), respectively. Air pollutants were positively associated with circulatory and pulmonary disease mortality, especially cerebrovascular disease. Each same-day PM(2.5) increase of 10 mu g/m(3) was associated with a 1.3% increase in cerebrovascular mortality rate (95% confidence interval: 0.2-2.4). Rate ratios were attenuated after the enforcement in most of the outcomes, probably due to reduced toxicity of the pollutants. In the crude interrupted time-series analysis, reductions of standardized mortality rates after the enforcement were the greatest in high traffic areas. Even after adjustment of longer-time trend, mortality rate from cerebrovascular disease was reduced by 8.50% (p&lt;.001) with dose-response relationship. However, the declines in other cause-specific mortality became equivocal. This natural experiment in Tokyo suggests that emission controls improved air quality. Although suggestive, further data are needed to conclusively demonstrate an impact on mortality rates. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.scitotenv.2011.06.002

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：B M J PUBLISHING GROUP  

Background The slow progress of tobacco control policy in Japan reflects the tension among the interests of the Finance Ministry (which remains the majority shareholder of Japan Tobacco, Inc), the Health Ministry, tobacco growers and consumers.
Methods We sought to examine regional disparities in compliance with national tobacco control legislation (the 2003 Health Promotion Law). Specifically, we sought to examine whether prefecture-level compliance with legislation was correlated with decreases in smoking prevalence, and decreases in lung cancer mortality rates. We also examined whether prefectural involvement in growing tobacco was associated with lower compliance with the law.
Results From 2001 to 2007, higher prefectural compliance with tobacco control laws was associated with decreased prevalence of smoking. Decreased tobacco consumption was in turn associated with declining lung cancer mortality. Prefectures involved in growing tobacco exhibited lower levels of compliance with national tobacco control laws. The same prefectures also exhibited the worst improvement in smoking prevalence.
Conclusions This study in Japan suggests that tobacco control policies are being unevenly implemented across prefectures, and that measures to counteract the influence of local tobacco culture are required to reduce the disparities in regional tobacco control outcomes in that country.

DOI： 10.1136/tc.2010.041442

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

In Japan in 1968, rice-oil contaminated by polychlorinated biphenyls and polychlorinated dibenzofurans caused severe food poisoning, termed "Yusho" (oil disease). Several previous studies attempted to evaluate the effects targeting officially-certified Yusho patients. However, these studies have several limitations such as the left-truncated nature of the registry or residual confounding arising from the referent population selection. We thus conducted an area-based standardized mortality ratios (SMRs) study using vital statistics. A severely affected area (Tamanoura area) was adopted as the exposure group, with a reference population from Nagasaki prefecture in Kyushu, which included the Tamanoura. A large number of residents in Tamanoura were exposed to the rice-oil (28% of all the certified cases as of 2009). We estimated SMRs of non-cancer and cancer diseases for the years 1968-2002. Shortly after the exposure, SMRs of all causes, diabetes mellitus, cardiovascular disease, pneumonia/bronchitis, and bronchus/lung cancer were elevated. In particular, SMRs of heart disease were 1.97 [95% confidence intervals (CI): 1.09-3.56] in 1968, 2.05 (95% Cl: 1.16-3.60) in 1969, and 1.89 (95% CI: 1.05-3.41) in 1975. However, we did not observe clear increase in SMRs more than 10 years after the exposure. This study provides further evidence in Yusho, especially on acute effects on non-cancer mortality. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.scitotenv.2011.05.038

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Introduction: It is well-known that prenatal or postnatal exposure to methylmercury can produce neurological signs in adults and children, exemplified by a case of large-scale poisoning in Minamata, Japan, in the 1950s. However, evidence regarding whether pre- or postnatal exposure to methylmercury causes psychiatric symptoms (e.g., impairment of intelligence and mood and behavioral dysfunction) is still limited-excluding cases of fetal Minamata disease patients.
Methods: We evaluated the effects of pre- or postnatal exposure to methylmercury on psychiatric symptoms using data derived from a 1971 population-based survey in Minamata and neighboring communities. We adopted residential areas as an exposure indicator and psychiatric symptoms as the outcome. Then, we estimated the adjusted prevalence odds ratio (POR) and confidence interval (Cl) of psychiatric symptoms in relation to residential area.
Results: There were 904 participants in Minamata (high exposure area), 1700 in Goshonoura (middle exposure area), and 913 in Ariake (low exposure area). Compared to the Ariake area, participants in the Minamata area manifested psychiatric symptoms more frequently: PORs for impairment of intelligence and mood and behavioral dysfunction were 5.2 (95% Cl: 3.7-7.3) and 4.4 (95% Cl: 2.9-6.7), respectively. Furthermore, participants with psychiatric symptoms in the Minamata area more frequently had neurological signs. Peaks in prevalence of psychiatric symptoms occurred around age 20 and in older age adults in the area. These findings did not change when we excluded those who had been officially certified as Minamata disease patients by that time.
Conclusions: The present study suggests a relationship between pre- or postnatal exposure to methylmercury and psychiatric symptoms among the general population in Minamata even after excluding officially certified patients. (C) 2011 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.envint.2011.03.008

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

An association between exposure to traffic-related air pollution and reduced birth weight has been suggested. However, previous studies have failed to adjust for maternal size, which is an indicator of individual genetic growth potential. Therefore, we evaluated the association of air pollution with birth weight, term low birth weight (term-LBW), and small for gestational age (SGA), with adjustment for maternal size. Individual data were extracted from a database that is maintained by a maternal and perinatal care center in Shizuoka, japan. We identified liveborn singleton births (n=14,204). Using geocoded residential information, each birth was assigned a number of traffic-based exposure indicators: distance to a major road; distance-weighted traffic density; and estimated concentration of nitrogen dioxide by land use regression. The multivariate adjusted odds ratios and their 95% confidence intervals (CIs) for the associations between exposure indicators and outcomes were then estimated using logistic regression models. Overall, exposure indicators of air pollution showed no clear pattern of association. Although there are many limitations, we did not find clear associations between birth-weight-related outcomes and the three markers of traffic-related air pollution. (C) 2011 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.envres.2011.02.005

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Few studies have examined the effects of mixed metal exposures in humans. We have evaluated the effect of prenatal lead exposure in a Faroese birth cohort in the presence of similar molar-level exposure to methylmercury. A cohort of 1022 singleton births was assembled in the Faroe Islands during 1986-1987 from whom lead was measured in cord-blood. A total of 896 cohort subjects participated in a clinical examination at age 7 and 808 subjects in a second examination at age 14. We evaluated the association between cord-blood lead concentrations and cognitive deficits (attention/working memory, language, visuospatial, and memory) using multiple regression models. Overall, the lead concentration showed no clear pattern of association. However, in subjects with a low methylmercury exposure, after inclusion of statistical interaction terms, lead-associated adverse effects on cognitive functions were observed. In particular, higher cord-blood lead was associated with a lower digit span forward score on the Wechsler Intelligence Scale for Children-Revised (WISC-R) [beta. = -1.70, 95% confidence interval (CI): -3.12 to -0.28] at age 7 and a lower digit span backward score on the WISC-R (beta. = -2.73, 95%CI: -4.32 to -1.14) at age 14. Some interaction terms between lead and methylmercury suggested that the combined effect of the exposures was less than additive. The present study indicates that adverse effects of exposure may be overlooked if the effects of a co-pollutant are ignored. The present study supports the existence of adverse effects on cognitive functions at prenatal lead exposures corresponding to an average cord-blood concentration of 16 μg/L. © 2010 Elsevier Inc.

DOI： 10.1016/j.ntt.2010.09.004

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Objective: Evidence linking short-term exposure to outdoor air pollution with hemorrhagic stroke is inconsistent. Methods: We evaluated the associations between outdoor air pollution and specific types of stroke in Tokyo, Japan, from April 2003 to December 2008. We obtained daily counts of stroke mortality (n = 41,440) and concentrations of nitrogen dioxide as well as particles less than 2.5 mu m in diameter. Time-series analysis was employed. Results: Although same-day air pollutants were positively associated with ischemic stroke and intracerebral hemorrhage mortality, both air pollutants were more strongly associated with subarachnoid hemorrhage mortality: rate ratio was 1.041 (95% confidence interval: 1.011-1.072) for each 10 mu g/m(3) increase in the previous-day particles less than 2.5 mu m. Conclusions: This study suggests that short-term exposure to outdoor air pollution increases the risks of hemorrhagic stroke mortality as well as ischemic stroke mortality.

DOI： 10.1097/JOM.0b013e3182099175

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Background: Preterm births cause a large public-health burden, and air pollution is considered to be a potential risk factor. We evaluated the association between proximity to major roads (as an index for air pollution) and preterm births, classified by gestational age and specific clinical manifestations.
Methods: Data on parental information and birth outcomes were extracted from the database maintained by the perinatal hospital in Shizuoka, Japan. We restricted the analysis to mothers who delivered liveborn single births from 1997 to 2008 (n = 14,226). Using the geocoded residential information, each birth was classified on its proximity to major roads. We estimated the multivariate-adjusted odds ratios and their 95% confidence intervals (CIs) for the association of proximity to major roads with preterm births, using logistic regression.
Results: We found positive associations between proximity to major roads and preterm births at all gestational ages. Living within 200 m increased the risk of births before 37 weeks by 1.5 times (95% CI = 1.2-1.8), birth before 32 weeks by 1.6 times (1.1-2.4), and births before 28 weeks by 1.8 times (1.0-3.2). Proximity specifically increased the risk of preterm births with preterm premature rupture of the membranes and with pregnancy hypertension.
Conclusions: This study demonstrates that exposure to traffic-related air pollution increases even the risk of preterm births of less than 30 weeks&apos; gestational age and proposes a possible mechanism.

DOI： 10.1097/EDE.0b013e3181fe759f

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Objectives Long-term exposure to inorganic arsenic is related to increased risk of cancer in the lung, skin, bladder, and, possibly, other sites. However, little is known about the consequences of developmental exposures in regard to cancer risk. During early summer in 1955, mass arsenic poisoning of infants occurred in the western part of Japan because of contaminated milk powder. Okayama Prefecture was most severely affected. We examined whether the affected birth cohorts in this prefecture experienced increased cancer mortality. Methods We targeted subjects who were born from September 1950 to August 1960 and died in Okayama Prefecture between January 1969 and March 2008 due to malignant neoplasm (N = 3,141). We then compared cancer mortality (total, liver, pancreatic, lung, bladder/ kidney, and hematopoietic cancers) between cohorts born before the milk poisoning (exposed group) and cohorts born after the poisoning (nonexposed group). We estimated mortality ratios and 95% confidence intervals. Results Total and liver cancers were elevated in the cohort up to 1 year of age at time of the poisoning. In addition, pancreatic and hematopoietic cancers were elevated in the cohorts up to 5 years of age, and mortality ratios were approximately twice those of the nonexposed group. Increased risk of lung and bladder/kidney cancers was not apparent. Conclusions Although dilution is present in these cohortbased data, our study highlights the notion that developmental arsenic exposure may lead to a different pattern of cancer, including increases in pancreatic and hematopoietic cancer, as compared with adult or lifetime exposures to inorganic arsenic. © 2010 The Japanese Society for Hygiene.

DOI： 10.1007/s12199-010-0182-x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MANEY PUBLISHING  

We investigated whether individuals exposed to asbestos by living near an asbestos-manufacturing facility experienced increased lung cancer mortality. We studied a neighborhood around such a plant in the central Japanese city of Hashima. From 1943 to 1991 this plant produced insulation and packing material using amosite- and chrysotile-type asbestos fibers. The study group was comprised of 577 households. We obtained demographic information by a questionnaire and determined the underlying cause of death for deceased household members from death certificates. Using hourly meteorological data from local observatories, we estimated relative asbestos concentrations in the plant's vicinity, determined the quartile boundaries, and designated each study subject's quartile of ambient exposure. Finally, we calculated standardized mortality ratios to evaluate the association of residential asbestos with lung cancer risk. Our findings strongly suggest that neighborhood asbestos exposure can increase the risk of lung cancer mortality in men and probably in women.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OKAYAMA UNIV MED SCHOOL  

Physicians should educate patients with sexually transmitted infections (STIs) on measures to prevent reinfection and should also undertake human immunodeficiency virus (HIV) testing after diagnosis of STIs. These preventive measures are important, but it is not known to what extent these procedures are followed in Japan. We conducted a cross-sectional study to investigate the proportion of patients with STIs who received appropriate management from physicians, namely recommendation of HIV testing, encouragement of condom use and examination and/or treatment of sexual partners, to elucidate the factors affecting institution of each measure. From a mailshot of 566 physicians, 409 (72.3%) responded, with 176 diagnosing an STI in 967 patients. The proportions applying the 3 measures were low (recommendation of HIV testing: 27.0%; encouragement of condom use: 64.8%; examination of sexual partners: 17.5%), and were related to the sex of the patients and numbers of patients diagnosed by the physicians. Female patients received better care than male patients, particularly with respect to recommendation of HIV testing (odds ratio: 2.82). Physicians who diagnosed more than 20 STI patients tended not to provide appropriate management. These findings suggest the necessity for better physician management of patients for effective prevention of STIs.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OKAYAMA UNIV MED SCHOOL  

Obesity in children is a serious public health problem, and TV viewing is considered a potential risk factor. Since, however, no relevant association studies have been conducted in Japan, we evaluated the association between TV viewing and obesity using a population-based study conducted in a Japanese town. All 616 preschool children in the town were enrolled in February 2008, and a self-administered questionnaire to collect children's and parents' characteristics was sent to the parents. We dichotomized the time spent TV viewing and evaluated associations by logistic regression using a "less than 2h" category as a reference. The questionnaire was collected from 476 participants (77.3%), of whom 449 were available for the final analyses. Among them, 26.9% of preschool children reported 2 or more hours of TV viewing per day and 8.2% were defined as obese. In logistic regression analyses, there was no positive association in unadjusted (odds ratio [OR] = 1.11, 95% confidence interval [95% CI]: 0.50-2.49) or adjusted models for exclusively breastfed status, sleep duration, or maternal factors (OR = 1.11, 95% CI: 0.50-2.51). We also found no positive association between TV viewing and overweight status, possibly owing to the influence of social environment, low statistical power, or misclassification.

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Background: Physical activity recommendations for older adults with poor health needs to be understood.
Purpose: This study aims to examine the association between the frequency of physical activity and mortality among a sample of elderly subjects, most of whom were under treatment for pre-existing disease.
Methods: Data on the frequency of leisure-time physical activity, walking for transportation, and non-exercise physical activity were obtained from a population-based cohort study in Shizuoka, Japan. Of the randomly selected 22,200 residents aged 65-84 years, 10,385 subjects were followed from 1999 to 2006 and analyzed. Hazard ratios (HRs) and 95% CIs were obtained for all-cause; cardiovascular disease (CVD); and cancer mortality, after adjusting for covariates such as preexisting disease(s) A subgroup analysis that was restricted to subjects under treatment for preexisting disease(s) at baseline was further conducted. Data were collected between 1999 and 2006, and all analyses were conducted in 2008 and 2009.
Results: Every physical activity was associated with a reduced risk of all-cause and CVD mortality, among not only the total sample but even those under treatment. The HRs for CVD mortality among participants with 5 or more days of non-exercise physical activity per week for the total sample and those with pre-existing disease(s) were 038 (95% CI=0.22, 0 55) and 0.35 (95% CI=0.24, 052), respectively, compared with no non-exercise physical activity. The association between physical activity and cancer mortality was not clear
Conclusions: This study suggests a protective effect of physical activity on all-cause and CVD mortality among Japanese elderly people with pre-existing disease (Am J Prev Med 2010;38(4) 410-418) (C) 2010 American Journal of Preventive Medicine

DOI： 10.1016/j.amepre.2009.12.033

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Objective: To evaluate the effects of outdoor air pollution, taking into account indoor air pollution, in Indonesia. Methods: The subjects were 15,242 children from 2002 to 2003 Indonesia Demographic and Health Survey. The odds ratios and their confidence intervals for adverse health effects were estimated. Results: Proximity increased the prevalence of acute respiratory infection both in urban and rural areas after adjusting for indoor air pollution. In urban areas, the prevalence of acute upper respiratory infection increased by 1.012 (95% confidence intervals: 1.005 to 1.019) per 2 km proximity to a major road. Adjusted odds ratios tended to be higher in the high indoor air pollution group. Conclusion: Exposure to traffic-related outdoor air pollution would increase adverse health effects after adjusting for indoor air pollution. Furthermore, indoor air pollution could exacerbate the effects of outdoor air pollution.

DOI： 10.1097/JOM.0b013e3181d44e3f

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：B M J PUBLISHING GROUP  

Objectives The number of studies investigating the health effects of long-term exposure to air pollution is increasing, however, most studies have been conducted in Western countries. The health status of Asian populations may be different to that of Western populations and may, therefore, respond differently to air pollution exposure. Therefore, we evaluated the health effects of long-term exposure to traffic-related air pollution in Shizuoka, Japan.
Methods Individual data were extracted from participants of an ongoing cohort study. A total of 14 001 older residents, who were randomly chosen from all 74 municipalities of Shizuoka, completed questionnaires and were followed from December 1999 to March 2006. Individual nitrogen dioxide exposure data, as an index for traffic-related exposure, were modelled using a land use regression model. We assigned participants an estimated concentration of nitrogen dioxide exposure during 2000-2006. We then estimated the adjusted HR and their Cl for a 10 mu g/m(3) increase in exposure to nitrogen dioxide for all-cause or cause-specific mortality.
Results The adjusted HR for all-cause mortality was 1.02 (95% Cl 0.96 to 1.08). Regarding cause-specific mortality, the adjusted HR for cardiopulmonary mortality was 1.16 (95% Cl 1.06 to 1.26); in particular the adjusted HR for ischaemic heart disease mortality was 1.27 (95% Cl 1.02 to 1.58) and for pulmonary disease mortality it was 1.19 (95% Cl 1.02 to 1.38). Furthermore, among non-smokers, a 10 mu g/m(3) increase in nitrogen dioxide was associated with a higher risk for lung cancer mortality (HR 1.30, 95% Cl 0.85 to 1.93).
Conclusion Long-term exposure to traffic-related air pollution, indexed by nitrogen dioxide concentration, increases the risk of cardiopulmonary mortality, even in a population with a relatively low body mass index and increases the risk of lung cancer mortality in nonsmokers.

DOI： 10.1136/oem.2008.045542

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

Recent studies suggest potential adverse effects of methylmercury exposure on cardiovascular disease, although the evidence of association with hypertension is still inconsistent. Therefore, we evaluated the effects of methylmercury exposure on hypertension in Minamata. We used data derived from the 1971 population-based survey in Minamata and neighboring communities. We also utilized data on hair mercury content of the participants (derived from a 1960 investigation). We adopted two exposure indices (residential area and hair mercury content) and two hypertension outcomes (past history of hypertension and hypertension defined by measurements in the examination). Then, we estimated the adjusted prevalence odds ratio (POR) and its confidence interval (CI) of both hypertension outcomes in relation to residential area and hair mercury content. In the Minamata area (high exposure area), 87% (833) of the eligible population (aged &gt;= 10 years) participated in the 1971 investigations. In the Goshonoura area (middle exposure area) and the Ariake area (low exposure area), 93% (1450) and 77% (755), respectively, of the eligible population participated. Compared with subjects in the Ariake area, the subjects in the Minamata area manifested hypertension more frequently, and PORs observed for two hypertension outcomes were 1.6 (95% CI: 1.2-2.1) and 1.4 (95% CI: 1.1-1.9), respectively. Furthermore, dose-response trends with hair mercury content were observed for both hypertension outcomes. The present finding supports the causal relationship between methylmercury exposure and hypertension. (C) 2009 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.envres.2009.10.011

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Severe methylmercury poisoning occurred in Minamata and neighboring communities in the 1950s and 1960s. The exposed patients manifested neurological signs, and some patients exposed in utero were born with so-called congenital Minamata disease. In a previous report, Nishigaki and Harada evaluated the methylmercury concentrations in the umbilical cords of inhabitants and demonstrated that methylmercury actually passed through the placenta (Nishigaki and Harada, 1975). However, the report involved a limited number of cases (only 35) and did not quantitatively evaluate the regional differences in the transition of methylmercury exposure. Therefore, in the present study, we evaluated the temporal and spatial distributions of methylmercury concentrations in umbilical cords, with an increased number of participants and additional descriptive analyses. Then, we examined whether the methylmercury concentrations corresponded with the history of the Minamata disease incident. A total of 278 umbilical cord specimens collected after birth were obtained from babies born between 1925 and 1980 in four study areas exposed to methylmercury. Then. we conducted descriptive analyses, and drew scatterplots of the methylmercury concentrations of all the participants and separated by the areas. In the Minamata area, where the first patient was identified in 1956, the methylmercury concentration reached a peak around 1955. Subsequently, about 5 years later, the concentrations peaked in other exposed areas with the expected exposure distribution corresponding with acetaldehyde production (the origin of methylmercury). This historical incident several decades ago in Minamata and neighboring communities clearly shows that regional pollution affected the environment in utero. Furthermore, the temporal and spatial distributions of the methylmercury concentrations in the umbilical cords tell us the history of the Minamata disease incident. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.scitotenv.2009.10.011

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DOI： 10.1016/j.annepidem.2009.06.003

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Objective. To investigate the associations between sleep duration and mortality in the elderly by controlling for sleep quality.
Method. Data were collected from participants in a cohort study in Shizuoka, Japan. A total of 14,001 elderly residents (aged 65-85 years), randomly chosen from all 74 municipalities in the prefecture. completed questionnaires that evaluated sleep duration, sleep complaints, and the use of hypnotics. Participants were followed from 1999 to 2006. We analyzed 11,395 subjects to estimate the hazard ratios (HR) for mortality from all causes and cardiovascular disease (CVD).
Results. With 60,252 person-years, 1004 deaths were identified. While short sleep duration and mortality were not associated, longer sleep duration was associated with higher risk of mortality in both sexes. Compared with those who slept 7 h, the multivariate HR and 95% confidence interval of CVD mortality for those who slept &gt;= 10 h was 1.95 (1.18-3.21) and, for those who slept &lt;= 5 h, it was 1.10 (0.62-1.93). Although no clear association was found between sleep quality and mortality, long sleep duration was associated with higher risk of CVD mortality among those with poor sleep quality.
Conclusion. Long sleep duration is associated with higher risk of CVD mortality among the elderly with poor sleep quality. (C) 2009 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.ypmed.2009.06.016

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Oseltamivir is a neuraminidase inhibitor that inhibits influenza virus proliferation, and is used as an antiviral drug against influenza A and B viruses. Recently, concerns have been raised about hallucinations, delirium, and abnormal activity after administration of oseltamivir for treatment of infection with influenza virus. A large epidemiologic study was conducted in Japan in the winter of 2006-2007 to assess the relationship between oseltamivir intake and adverse behaviors, and an interim report was released on 10 July 2008. In the report, the research group concluded that no positive associations were detected between oseltamivir intake and abnormal behaviors. However, the analytic method used in the study was flawed. A correct analysis (based on person-time) shows a rate ratio of 1.57 (95% confidence interval = 1.34-1.83). This example clearly illustrates the importance of person-time in the analysis of cohort studies.

DOI： 10.1097/EDE.0b013e3181a3d3f6

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A land use regression (LUR) model has been used successfully for predicting traffic-related pollutants, although its application has been limited to Europe and North America. Therefore, we modeled traffic-related pollutants by LUR then examined whether LUR models could be constructed using a regulatory monitoring network in Shizuoka, Japan. We used the annual-mean nitrogen dioxide (NO(2)) and suspended particulate matter (SPM) concentrations between April 2000 and March 2006 in the study area. SPM accounts for particulate matter with an aerodynamic diameter less than 8 mu m (PM8). Geographic variables that are considered to predict traffic-related pollutants were classified into four groups: road type, traffic intensity, land use, and physical component. Using geographical variables, we then constructed a model to predict the monitored levels of NO(2) and SPM. The mean concentrations of NO(2) and SPM were 35.75 mu g/m(3) (standard deviation of 11.28) and 28.67 mu g/m(3) (standard deviation of 4.73), respectively. The final regression model for the NO(2) concentration included five independent variables. R(2) for the NO(2) model was 0.54. On the other hand, the regression model for the SPM concentration included only one independent variable. R(2) for the SPM model was quite low (R(2) = 0.11). The present study showed that even if we used regulatory monitoring air quality data, we could estimate NO(2) moderately well. This result could encourage the wide use of LUR models in Asian countries. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.scitotenv.2008.12.038

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Background: Large-scale methylmercury poisonings have occurred in Japan (Minamata and Niigata) and in Iraq. The current WHO threshold for adult exposure (hair level: 50 mu g/g) was based on evidence from Niigata, which included only acute and severe cases. That study leaves open the possibility of more subtle effects at lower exposure levels.
Methods: The Shiranui sea had been contaminated in the 1950s by the discharge of methylmercury from a factory near Minamata.
In 1960, the hair mercury content of 1694 residents living on the coastline of the Shiranui sea was measured by researchers from the Kumamoto Prefecture Institute for Health Research. Independently, in 1971, a population-based study to examine neurologic signs was conducted in the Minamata and Goshonoura areas, on the coastline of the Shiranui Sea, and the Ariake area (reference), by researchers at Kumamoto University. We identified 120 residents from exposed areas who were included in both datasets, plus 730 residents of Ariake (an unexposed area) who were also examined for neurologic signs.
Results: Hair mercury levels were associated with perioral sensory loss in a dose-response relationship. The adjusted prevalence odds ratios and 95% confidence intervals for perioral sensory loss, compared with the lowest exposure category (0-10 mu g/g), were 4.5 (0.5-44), 9.1 (1.0-83), and 10 (0.9-110), for the dose categories &gt;10 to 20, &gt;20 to 50, and &gt;50 mu g/g, respectively. The prevalence of all neurologic signs was higher in the exposure area than in Ariake.
Conclusions: An increased prevalence of neurologic signs, especially perioral sensory loss, was found among residents with hair mercury content below 50 mu g/g.

DOI： 10.1097/EDE.0b013e318190e73f

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To investigate the effect of exclusive breastfeeding on the likelihood of Japanese preschool children being overweight, population-based cross-sectional survey data from M town in Japan were used. Using the population registry of this town, all 616 preschool children were identified, and a self-administered questionnaire was sent to their parents. The exposure variable of interest was exclusive breastfeeding from. birth to 6 months, and the outcome variable of interest was the children being overweight at preschool age. Statistical analyses used included logistic regression and sensitivity analyses. In the final analyses, we included 448 preschool children. Although all point estimates indicated a protective effect, logistic regression analyses showed no significant reduction in being overweight due to exclusive breastfeeding in the unadjusted model (odds ratio (OR)= 0.70, 95% confidence intervals: 0.30-1.64), the model adjusted for birth weight (OR = 0.70, 95% CI: 030-1.63), the model adjusted for child lifestyle (OR = 0.71, 95% CI: 0.30-1.67), or the model adjusted for parental factors (OR=0.46, 95% CI: 0.15-1.37). In sensitivity analyses, point estimates were not significant, but a protective effect was observed. In conclusion, our results suggest that breastfeeding might have a protective effect on Japanese preschool children against being overweight, although statistical significance was not observed due to the limitation of the statistical power of the findings.

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Background: It is well known that large-scale poisonings caused by methylmercury occurred in Japan (Minamata, in the 1950s) and Iraq. However, in contrast to Iraq, there have been few sound epidemiologic studies in Minamata. We evaluated the effect of methylmercury on neurologic signs using data from a 1971 population-based study.
Methods: Villages in 3 areas were selected for study: the Minamata area (a high-exposure area), the Goshonoura area (a medium-exposure area), and the Ariake area (a low-exposure area). We used place of residence as the-exposure indicator. We examined associations between methylmercury exposure and the following neurologic signs measured on clinical examination: paresthesia of whole body, paresthesia of extremities, paresthesia around the mouth, ataxia, dysarthria, tremors, and pathologic reflexes.
Results: Total population was 1120 in the high-exposure villages, 1845 in the medium-exposure villages, and 1165 in the low-exposure villages. In the Minamata area, 87% (n = 833) of the eligible population (age 10 years and older) participated in the 1971 investigations, in the Goshonoura area, 93% (n = 1450), and in the Ariake area, 77% (n = 755). Compared with subjects in the Ariake area, the subjects in the Minamata area manifested neurologic signs more frequently. The highest prevalence odds ratio was observed for paresthesia around the mouth (110; 95% confidence interval = 16-820). Although residents in the Goshonoura area had been exposed less heavily than those in the Minamata area, Goshonoura residents also had increased prevalence of neurologic signs.
Conclusion: Long-term exposure to methylmercury has a strong adverse impact on neurologic signs among residents in a local community.

DOI： 10.1097/EDE.0b013e31815c09d2

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Objective Methyl-mercury (MeHg) was discharged from a chemical factory in Minamata, and consequently spread throughout the Shiranui Sea in Kumamoto, Japan. Although many studies have focused on MeHg-induced neurological disorders, the association between MeHg and malignant neoplasms has not been adequately investigated. Therefore, we explored this association using the age standardized mortality ratio (ASMR) in an ecologic study over a wide area allowing for a long empirical induction period.
Methods The subjects were residents in areas around the Shiranui Sea. We divided these areas into exposure groups 1 (Minamata and Ashikita regions) and 2 (Amakusa region). Exposure group 1 was contaminated from the late 1930s, and exposure group 2 was contaminated from the late 1950s. In addition, exposure group 1 was contaminated more heavily than exposure group 2. There were 92,525 and 152,541 residents in each group in 1960, respectively. We analyzed the cancer ASMR in both exposure groups using data from two reference populations (Japan and Kumamoto prefecture) from 1961 to 1997. There were 94,301,494 and 1,856,192 people in each reference group in 1960, respectively. We abstracted population and mortality data from the censuses and the vital statistics of the prefecture and Japan.
Results An increased leukemia ASMR and a decreased gastric cancer ASMR were observed in both exposure groups, while other ASMRs were around unity and less precise. Furthermore, the leukemia ASMRs were elevated differently between the two exposure groups: the leukemia ASMR was already elevated early in the study period in exposure group 1 and increased gradually in exposure group 2.
Conclusion While the negative association between MeHg and gastric cancer might be explained by salt intake, the positive association between MeHg and leukemia could not be explained by potential confounders. Despite some limitations mainly due to its ecologic design, this study indicates the necessity of an individual-level study evaluating the association between MeHg and leukemia in regions with exposure to MeHg.

DOI： 10.1007/s00420-007-0179-y

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：HELDREF PUBLICATIONS  

Among industrialized countries, Japan still maintains an old set of guidelines for particulate matter (PM); therefore, we assessed the public health impacts of PM exposure in various Situations using data from the Tokyo metropolitan area. Subjects were 7.8 million people aged older than 30 years. Based on a linear relationship between exposure and health effects, we estimated attributable cases of mortality caused by PM. Even at the recent exposure level, the number of deaths will occur after both short- and long-term exposure. When the guideline for PM2.5 (particles &lt; 2.5 mu m in diameter) long-term exposure was set at 12 mu g/m3, we could prevent 8% of all causes mortality or 6,700 deaths in the Tokyo metropolitan area per year. This assessment shows that guidelines for long-term exposure, especially for PM2.5, should be recommended in Japan.

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DOI： 10.11197/jaih.27.183

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DOI： 10.1265/jjh.64.786

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DOI： 10.1265/jjh.64.796

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