粒子状物質への短期曝露が人の疾患に及ぼす単独影響および相互影響に関する疫学的アプローチを用いた検討

京都大学0048新制・課程博士博士(工学)甲第21362号工博第4521号新制||工||1704(附属図書館)京都大学大学院工学研究科都市環境工学専攻(主査)教授 高野 裕久, 教授 米田 稔, 准教授 上田 佳代学位規則第4条第1項該当Doctor of Philosophy (Engineering)Kyoto UniversityDFA

Effect modification by temperature on the association between O3 and emergency ambulance dispatches in Japan: A multi-city study

Numerous epidemiological studies have reported that ozone (O₃) and temperature are independently associated with health outcomes, but modification of the effects of O₃ on health outcomes by temperature, and vice versa, has not been fully described. This study aimed to investigate effect modification by temperature on the association between O₃ and emergency ambulance dispatches (EADs) in Japan. Data on daily air pollutants, ambient temperature, and EADs were obtained from eight Japanese cities from 2007 to 2015. A distributed lag non-linear model combined with Poisson regression was performed with temperature as a confounding factor and effect modifier to estimate the effects of O₃ on EADs at low (75th percentile) temperature for each city. The estimates obtained from each city were pooled by random-effects meta-analysis. When temperature was entered as a confounder, the estimated effects of O₃ on EADs for all acute, cardiovascular, and respiratory illnesses were largest at lag 0 (current-day lag). Therefore, this lag was used to further estimate the effects of O₃ on EADs in each temperature category. The estimated effects of O₃ on EADs for all acute, cardiovascular, and respiratory illnesses in all eight Japanese cities increased with increasing temperature. Specifically, a 10 ppb increase in O₃ was associated with 0.80 % (95 % CI: 0.25 to 1.35), 0.19 % (95 % CI: -0.85 to 1.25), and 1.14 % (95 % CI: -0.01 to 2.31) increases in the risk of EADs for all acute, cardiovascular, and respiratory illnesses, respectively, when city-specific daily temperature exceeded the 75th percentile. Our findings suggest that the association between O₃ and EADs for all acute, cardiovascular, and respiratory illnesses is the highest during high temperature. Finding of this study can be used to develop potential mitigation measures against O₃ exposure in high temperature environment to reduce its associated adverse health effects

Acute Effects of Ambient PM2.5 on All-Cause and Cause-Specific Emergency Ambulance Dispatches in Japan

Short-term health effects of ambient PM₂.₅ have been established with numerous studies, but evidence in Asian countries is limited. This study aimed to investigate the short-term effects of PM₂.₅ on acute health outcomes, particularly all-cause, cardiovascular, respiratory, cerebrovascular and neuropsychological outcomes. We utilized daily emergency ambulance dispatches (EAD) data from eight Japanese cities (2007–2011). Statistical analyses included two stages: (1) City-level generalized linear model with Poisson distribution; (2) Random-effects meta-analysis in pooling city-specific effect estimates. Lag patterns were explored using (1) unconstrained-distributed lags (lag 0 to lag 7) and (2) average lags (lag: 0–1, 0–3, 0–5, 0–7). In all-cause EAD, significant increases were observed in both shorter lag (lag 0: 1.24% (95% CI: 0.92, 1.56)) and average lag 0–1 (0.64% (95% CI: 0.23, 1.06)). Increases of 1.88% and 1.48% in respiratory and neuropsychological EAD outcomes, respectively, were observed at lag 0 per 10 µg/m3 increase in PM₂.₅. While respiratory outcomes demonstrated significant average effects, no significant effect was observed for cardiovascular outcomes. Meanwhile, an inverse association was observed in cerebrovascular outcomes. In this study, we observed that effects of PM₂.₅ on all-cause, respiratory and neuropsychological EAD were acute, with average effects not exceeding 3 days prior to EAD onset

Long-term air pollution exposure and serum lipids and blood sugar: A longitudinal cohort study from the electricity generating authority of Thailand study

Only a few studies have investigated the association between long-term exposure to air pollution and alterations of serum lipids and blood sugar level in developing countries. The present longitudinal study examined associations between long-term air pollution exposure and serum lipids [total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C)] and fasting glucose (FG) in workers of the Electricity Generating Authority of Thailand (EGAT) in the Bangkok metropolitan region (BMR) of Thailand. We performed secondary analyses using the data obtained from 1, 839 participants (mean age, 58.3 years as of 2002) of the EGAT1 cohort study (2002–2012). The average concentration of each air pollutants (PM₁₀, O₃, NO₂, SO₂, and CO) at the sub-district level in BMR from 2002 to 2012 were estimated using the ordinary kriging method. Exposure periods were averaged to 3 months prior to laboratory testing. Linear mixed effects models were used to estimate associations between air pollution and serum lipids and blood sugar. After controlling for potential confounders, an interquartile range increment of PM₁₀, SO₂, and CO was associated with elevated LDL-C [6.6% (95%CI: 4.3, 9.0), 11.1% (7.2, 15.2), and 1.9% (1.1, 2.7), respectively] and FG [2.8% (1.5, 4.2), 6.8% (4.5, 9.1), and 1.1% (0.6, 1.5), respectively]. In addition, PM10, SO2, and CO were inversely associated with HDL-C [-1.8% (−3.7, 0.1), −3.3% (−6.2, −0.3), and −1.1 (−1.7, −0.5), respectively]. O₃ was negatively associated with TC, LDL-C, TG, and FG. These findings suggest inhalation of air pollutants may increase the risk of impaired metabolism of glucose and lipids

Long-term air pollution exposure and self-reported morbidity:a longitudinal analysis from the Thai cohort study (TCS)

Several studies have shown the health effects of air pollutants, especially in China, North American and Western European countries. But longitudinal cohort studies focused on health effects of long-term air pollution exposure are still limited in Southeast Asian countries where sources of air pollution, weather conditions, and demographic characteristics are different. The present study examined the association between long-term exposure to air pollution and self-reported morbidities in participants of the Thai cohort study (TCS) in Bangkok metropolitan region (BMR), Thailand.This study was supported by the International Collaborative Research Grants Scheme with joint grants from the Wellcome Trust UK (grant number GR071587MA) and the Australian National Health and Medical Research Council (NHMRC) (grant number 268055). It was also supported by a global health grant from the NHMRC (grant number 585426)