Heat stress and the incidence of chronic kidney disease: an ecological study using the universal thermal climate index
Description
Long-term, repeated exposure to heat stress may contribute to chronic kidney disease (CKD), yet global evidence remains limited. In this ecological study, we aimed to examine the association of different categories of heat stress, as well as the overall heat stress score, with the incidence of CKD at the country/region level. Data from 174 countries/regions were analyzed. Annual numbers of days with moderate, strong, very strong, and extreme heat stress in each country/region between 1990 and 2021 were assessed using the Universal Thermal Climate Index. A weighted heat stress score was generated from these counts. Linear mixed-effects models were used to evaluate the association between heat stress score and CKD incidence. The results showed that all heat stress categories were positively associated with CKD incidence. In models using the weighted heat stress score, each standard deviation increase in the score was associated with an estimated 0.890 (95% CI: 0.717–1.063) additional incident cases per 100,000 population. In this ecological study, we observed country/region-level associations between heat stress and CKD incidence; nevertheless, further validation is warranted.