Objective: In China, there is a lack of evidence regarding the effects of extreme temperatures on cause-specific cardiovascular mortality. Methods: Between 2007 and 2009, we gathered information from Beijing and Shanghai, China, including daily mortality rates for cardiovascular, cerebrovascular, ischemic, and hypertensive diseases, air pollution levels, and weather conditions. To investigate the effects of extremely high and low ambient temperatures on cause-specific cardiovascular mortality, we employed a distributed lag non-linear Poisson regression model.
Results: Beijing had stronger effects of cold and heat for all cause-specific cardiovascular mortality than Shanghai. The strongest cold effects on cause-specific cardiovascular mortality occurred between lags 0 and 27, while the strongest hot effects occurred between lags 0 and 14. In the two cities, the types of deaths affected by extremely low and high temperatures varied. In Beijing, hypertension was especially susceptible to extremely high and low temperatures; whereas individuals with ischemic heart disease exhibited the greatest relative risk in Shanghai (RRs = 1.16, 95 percent CI: 1.34) to a very low temperature.
Conclusion: In Beijing, extremely low and high temperatures were particularly dangerous for people with hypertension. In Shanghai, people with ischemic heart disease were more susceptible to extremely cold days.
Share this article