title: Comprehensive approach to understand the association between diurnal temperature range and mortality in East Asia.
abstract: An adverse association between diurnal temperature range (DTR) and mortality has been suggested, but with variable relationships in different cities. Comprehensive approaches to understanding the health effects of DTR using multinational data are required. We investigated the association between DTR and cause-specific mortality in an age-specific population and assessed the dependency of the health effects of DTR on geographic and climatic factors. Poisson generalized linear regression analyses with allowances for over-dispersion were applied to daily DTR and cause-specific mortality data from 30 cities in China, Japan, Korea, and Taiwan between 1979 and 2010, adjusted for various climatic and environmental factors. City-specific effects of DTR were estimated and summarized for the overall effects using geographic and climatic determinants in a meta-analysis. For all-cause, circulatory, and respiratory mortality, the greatest city-specific effects per 1°C DTR were found in Tianjin, China (1.80%; 95% confidence interval [CI]: 0.48, 3.14); Tangshan, China (2.25%; 95% CI: 0.65, 3.87); and Incheon, Korea (2.84%; 95% CI: 0.04, 5.73), respectively, and overall effects across 30 cities were 0.58% (95% CI: 0.44, 0.72), 0.81% (95% CI: 0.60, 1.03), and 0.90% (95% CI: 0.63, 1.18), respectively. Using quartile cutoff values for climatic (DTR, and mean temperature) and geographic (latitude, and longitude) characteristics, we divided the 30 cities into 4 different groups and conducted a meta-analysis within the groups using either a random or fixed effects model. Adverse effects of DTR were more pronounced for those aged ≥65years and varied according to geographic, longitudinal (0.07%; 95% CI: 0.05, 0.10), and climatic characteristics and the scale of DTR (0.33%; 95% CI: 0.12, 0.55) for overall all-cause mortality. The DTR is a risk factor affecting human health, depending on geographic location and the temperature variation, with particular vulnerability in aged populations.
authors.affiliation: School of Public Health, Seoul National University, Seoul, South Korea.
authors.forename: Jayeun
authors.initials: J
authors.lastname: Kim
authors.affiliation: School of Public Health, Seoul National University, Seoul, South Korea.
authors.forename: Jihye
authors.initials: J
authors.lastname: Shin
authors.affiliation: Institute of Environmental Medicine, Seoul National University Medical Research Center, Seoul, South Korea; Environmental Health Center, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Youn-Hee
authors.initials: YH
authors.lastname: Lim
authors.affiliation: Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Honda
authors.affiliation: Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Hashizume
authors.affiliation: Institute of Occupational Medicine and Industrial Hygiene and Department of Environmental and Occupational Medicine, National Taiwan University, Taipei City, Taiwan.
authors.forename: Yue Leon
authors.initials: YL
authors.lastname: Guo
authors.affiliation: Department of Environmental Health, School of Public Health, Fudan University, Shanghai, China.
authors.forename: Haidong
authors.initials: H
authors.lastname: Kan
authors.affiliation: School of Public Health, Seoul National University, Seoul, South Korea.
authors.forename: Seungmuk
authors.initials: S
authors.lastname: Yi
authors.affiliation: School of Public Health, Seoul National University, Seoul, South Korea; Institute of Health and Environment, Seoul National University, Seoul, South Korea. Electronic address: hokim@snu.ac.kr.
authors.forename: Ho
authors.initials: H
authors.lastname: Kim
mesh_terms: D002947:Cities; D005202:Asia, Eastern; D006801:Humans; D008962:Models, Theoretical; D009026:Mortality / Q000639:trends*; D012044:Regression Analysis; D012307:Risk Factors; D013696:Temperature; D013997:Time Factors
keywords: Climatic determinant; Diurnal temperature range; Lag effect; Mortality; Temperature variation