Impact of Extreme Heat on Cardiovascular Health in Kuwait: Present and Future Projections.

Background: The Middle East, especially Kuwait, is experiencing rapidly rising temperatures due to climate change. Cardiovascular diseases (CVD) are the leading cause of mortality in the country, and extreme heat is expected to exacerbate hospitalizations for cardiovascular diseases. There is limited data quantifying the historical and future impacts of heat on hospitalizations for cardiovascular diseases in Kuwait.

Methods: We collected daily hospital admission data of cardiovascular diseases in Kuwait from 2010 to 2019. We modeled the relationship between temperature and cardiovascular disease hospitalizations using distributed lag non-linear models (DLNMs), adjusting for relative humidity and seasonality. Future temperature projections for Kuwait under moderate and extreme climate change scenarios were obtained from the Coupled Model Inter-comparison Project Phase 6 (CMIP6), and the impact on cardiovascular disease hospitalizations was extrapolated for every decade until 2099.

Results: During the baseline period (2010-2019), a total of 263,182 CVD cases were recorded. Of which, 20,569 (95% eCI: 3,128, 35,757) were attributed to heat. We found that the relative risk of hospitalization for CVD increased from 1.292 (95% CI: 1.051, 1.589) at 41 °C to 1.326 (95% CI: 1.006, 1.747) at 43 °C, compared to the minimum morbidity temperature. Projections showed that, under moderate climate scenarios, CVD hospitalizations would increase by 1.96% by 2090-2099, while under extreme scenarios, the increase could reach 4.44%.

Conclusions: Extreme heat significantly contributes to CVD hospitalizations in Kuwait. This burden is projected to increase under climate change. Findings highlight the urgent need for healthcare system preparedness to mitigate the future health impacts of rising temperatures in Kuwait.