Résumé
Objective: To study the effect of diurnal temperature range on the number of elderly inpatients with ischemic stroke in Hunan Province. Method: Demographic and disease data, meteorological data, air quality data, population, economic and health resource data of elderly inpatients with ischemic stroke were collected in 122 districts/counties of Hunan Province from January to December 2019. The relationships between the diurnal temperature range and the number of elderly inpatients with ischemic stroke were analyzed by using the distributed lag non-linear model, including the cumulative lag effect of the diurnal temperature range in different seasons, extremely high diurnal temperature range and extremely low diurnal temperature range. Results: In 2019, 152 875 person-times were admitted to the hospital for ischemic stroke in the elderly in Hunan Province. There was a non-linear relationship between the diurnal temperature range and the number of elderly patients with ischemic stroke, with different lag periods. In spring and winter, with the decrease in diurnal temperature range, the risk of admission of elderly patients with ischemic stroke increased (Ptrend<0.001, Ptrend=0.002);in summer, with the increase in diurnal temperature range, the risk of admission of elderly patients with ischemic stroke increased (Ptrend=0.024);in autumn, the change in the diurnal temperature range would not cause a change in admission risk (Ptrend=0.089). Except that the lag effect of the extremely low diurnal temperature range in autumn was not obvious, the lag effect occurred in other seasons under extremely low and extremely high diurnal temperature ranges. Conclusion: The high diurnal temperature range in summer and the low diurnal temperature range in spring and winter will increase the risk of admission of elderly patients with ischemic stroke, and the risk of admission of elderly patients with ischemic stroke will lag under the extremely low and extremely high diurnal temperature ranges in the above three seasons.