Mapping the Burden of Ischemic Stroke Attributable to Temperature Variation under Climate Change Scenarios Accounting for Long-Term Adaptation

Abstract

With the intensification of climate change, temperature variability (TV), a critical climatic dimension, is projected to increase. As a climate-sensitive disease, ischemic stroke may be affected by temperature variability; however, the evidence on the ischemic stroke burdens of short-term temperature variability in a changing climate remains unknown, especially accounting for long-term exposure adaptation. Based on a nationally representative, multicenter data set of over 1.6 million individual-level, hourly data on ischemic stroke onset from 2015 to 2022, we adopted a case-crossover study design to evaluate the association between short-term exposure to TV and ischemic stroke onset using conditional logistic regression. Furthermore, we took the long-term TV adaptation into account to derive the modified nonlinear exposure-response function and evaluated the ischemic stroke burden under different climate change scenarios. Short-term exposure to TV was positively associated with the risk of ischemic stroke onset, and long-term TV significantly modified the effects with populations living in regions of persistently high TV being more vulnerable. The ischemic stroke cases attributable to TV have more than doubled from 2000 to 2020. Under the high-emission scenario (SSP5-8.5), the attributable fraction of ischemic stroke is projected to increase substantially (19–58%) by the end of the century, particularly in vulnerable regions such as Southwest and South China. These findings demonstrate that individuals have limited adaptive capacity to temperature variability. Incorporating temperature variability into climate–health risk assessments, public health preparedness, and mitigation strategies will be essential to safeguard populations in an increasingly unstable climate system.