Effect of ambient temperature on mortalities of ischemic stroke and hemorrhagic stroke in Beijing: a time series study
10.3760/cma.j.cn112338-20230310-00137
- VernacularTitle:气温对北京市居民缺血性卒中和出血性卒中死亡影响的时间序列研究
- Author:
Runhua ZHANG
1
;
Jing WANG
;
Gang LI
;
Gaifen LIU
Author Information
1. 首都医科大学附属北京天坛医院，北京 100070
- Keywords:
Temperature;
Stroke;
Mortality
- From:
Chinese Journal of Epidemiology
2023;44(11):1802-1807
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To assess the effect of ambient temperature on mortalities of ischemic stroke and hemorrhagic stroke in Beijing, China.Methods:The stroke mortality surveillance data and meteorological data in Beijing from January 1, 2014 to December 31, 2019 were collected. Distributed lag nonlinear models were used to estimate the cumulative effects of ambient temperature on stroke mortality, including ischemic stroke and hemorrhagic stroke after adjusting for temporal trend, day of week, air pollution, and relative humidity. Stratified analysis was conducted to evaluate whether sex and age modify the effect.Results:From 2014 to 2019, a total of 99 222 stroke deaths occurred in Beijing, including 69 327 ischemic stroke deaths, 24 954 hemorrhagic stroke deaths, and 4 941 unspecific stroke deaths. Using distributed lag nonlinear models, it was found the effect of temperature on stroke mortality was nonlinear and lagged. The ischemic stroke mortality risk analysis shows that with the minimum ambient temperature (MMT) for mortality (10.0 ℃) as reference, the effect of extreme low temperature (-6.2 ℃) was lagged and the relative risk ( RR) was highest at lag 0-21 days ( RR=1.26, 95% CI:1.04-1.51). The effect of extreme high temperature occurred with a lag of 0-3 days, and the cumulative RR value was 2.13 (95% CI: 1.72-2.62) at lag 0-14 days. The hemorrhagic stroke mortality risk analysis shows that with the MMT for mortality (28.0 ℃) as reference, the RR of extreme low temperature on stroke mortality was highest at lag 0-21 days ( RR=2.14, 95% CI: 1.23-3.70), and the effect of extreme high ambient temperature was short and only has statistical significance in the cumulative effect with a lag of 0-3 days ( RR=1.14, 95% CI: 1.01-1.28). Stratified analysis revealed that the effects of extreme and moderate low ambient temperature on hemorrhagic stroke death were higher in women compared to men, and the difference is statistically significant. Extreme high ambient temperature might increase the risk of ischemic stroke deaths in populations of different genders and age groups. Conclusions:The effect of low ambient temperature on ischemic stroke mortality was lagged, and the effect on hemorrhagic stroke was persistent. The effect of high ambient temperature on ischemic stroke mortality was persistent, but more transient on hemorrhagic stroke mortality. Sex and age might modify the effect of ambient temperature on stroke mortality.
