Associations of heatwaves and their characteristics with ischaemic stroke hospital admissions

This study collected data on daily meteorological conditions, air pollution levels, and IS admissions in Hunan Province from 2018 to 2019. A generalized additive model and a distributed lag nonlinear model were applied to examine the associations between heatwaves and Ischaemic stroke (IS) hospitalizations. In total, 329,876 IS admissions were analyzed over the study period.

The findings indicate that heatwaves significantly increased the risk of hospitalization for IS. The highest single-day lag risk was observed at a daily average temperature of 30.88℃ (RR = 1.05, 95% CI: 1.04-1.06) and at a daily maximum temperature of 35.82℃ (RR = 1.05, 95% CI: 1.03-1.06). Using the 5th and subsequent days of a heatwave as a reference, the 1st-2nd days (RR = 1.07, 95% CI: 1.02-1.12) and the 3rd-4th days (RR = 1.68, 95% CI: 1.03-1.10) were associated with an increased risk of IS hospitalization. Furthermore, the first (RR = 1.27, 95% CI: 1.19-1.35) and second (RR = 1.24, 95% CI: 1.16-1.32) heatwaves had a greater impact on IS hospitalization risk compared to the third and subsequent heatwaves.