Impact of Diurnal Temperature Range on Cardiovascular Disease Hospital Admissions among Chinese Farmers in Dingxi(the Northwest China)

Abstract Background: Diurnal temperature range (DTR), an important index of climate change, has been widely applied in exploring its effect on cardiovascular disease (CVD). However, few studies have investigated the correlations between DTR and CVD in poor rural areas in China. Methods: Therefore, using a distributed lag nonlinear model and a Poisson regression model, we evaluated this relationship among farmers living in the city of Dingxi (Northwest China). From 2016 to 2019, we obtained outpatient visits for CVD and meteorological data from the New Rural Cooperative Medical Insurance of Gansu Province (NRCMI) and Meteorological Science Data Sharing Service, respectively. The effects of DTR were examined in subgroups stratified by gender and age. Results: We observed nonlinear M-patterns between DTR and CVD hospitalizations among all subgroups when DTR was at the median level (13°C). Estimated effect of a relatively low DTR (5th percentile, 4°C) on the hospital admissions of CVD was stronger than the effect of a relatively high DTR (95th percentile, 19°C). We also found that the adverse effect of DTR on CVD risk was more pronounced in females and elderly than males and younger adults at the low DTR, and vice versa at the high DTR. Conclusions: These results could guide the local authorities to improve CVD preventive strategies in the rural areas.