The Impact of Diurnal Temperature Range and Years of Life Lost in Six Major Cities in South Korea

Abstract

TPS 661: Climate change: temperature effects 1, Exhibition Hall, Ground floor, August 26, 2019, 3:00 PM - 4:30 PM Background/Aim: Diurnal temperature range (DTR) is an important weather-related indicator of global climate change. Numerous studies have found DTR-mortality association, but there is little evidence regarding the association of DTR with years of life lost (YLL). Therefore, this study aims to examine the burden of DTR on YLL in six major cities of South Korea. Methods: This study was conducted in Seoul, Busan, Daegu, Incheon, Gwangju, Daejeon from 2001 to 2010. The DTR which describes the within-day temperature variability was derived as the difference between the daily maximum and daily minimum temperatures. Daily YLL were computed by matching the sex and age to the life tables of Korea and were then summed to yield the YLL for all deaths on the same day. We controlled for relative humidity, air pressure, sunshine duration, day of week, seasonality and long-term trends. Time-series generalized additive model (GAM) was used with a Gaussian regression to daily YLLs and a quasi-Poisson regression to daily deaths which were for comparison with YLL. Distributed lag non-linear model was incorporated in the GAM regression to control for the lagged and nonlinear effects of ambient temperatures. Also, we performed stratified analyses by sex and age groups. Results: The average daily mean temperature and daily mean DTR of Seoul were 12.8°C and 7.6°C. We observed YLL effects associated with DTR were higher in males than females and the youth (0-64 years old) than the elderly. DTR-associated with YLL showed 4.2 and 3 years in Seoul and Busan. Conclusions: This study found that DTR was associated with YLL and it highlights that the impact of DTR on YLL should be considered in public health policies and climate change research. Special interventions such as minimizing exposure to a higher DTR are necessary for vulnerable populations to reduce DTR-related YLL.