Background The rise in global temperature poses significant health risks, particularly for those working outdoor in hot weather. This study examines the impact of heat exposure on working people in Uddanam, Andhra Pradesh, India, known for its high chronic kidney disease (CKD) prevalence. Materials and Methods This cross-sectional study assessed heat exposure in 596 participants in various occupations in 36 Uddanam villages. Wet bulb globe temperature (WBGT) assessed heat exposures alongside heat stress perception and health impacts during cooler and hotter seasons. A subset was tested for blood and urine to assess kidney function. Results Participants were mostly males (60.1%) with a median age of 42 years. Among them, 49% were illiterate, 26% smokers, and 41% consumed alcohol. WBGT values were 31.7±2.2°C and 25.5±2.5°C in the hotter and cooler seasons, respectively. Occupational heat exposure varied significantly, with agriculture, brick kiln, and construction workers experiencing highest WBGT exposures. WBGT-Threshold limit values were exceeded by 16.7% and 100% workers in cooler vs. hotter seasons, respectively. Most (98.5%) had excessive heat exposure, reporting 5.7 times more heat-related symptoms. Heat stress index cross-shift changes were greater in heat-exposed participants (OR: 2.4; 95% CI: 1.6–3.5). Among 266 individuals, 76% had eGFR <90mL/min/1.73m 2 , with heat-exposed workers showing increased risk (OR 2.1, 95% CI: 1.1–3.7). Conclusion This study shows the health consequences of heat exposure in workers from CKDu hotspots like Uddanam, and the necessity for targeted heat stress mitigation and kidney health protection strategies. Further research is needed to determine the causal links between heat exposure and CKDu progression.
Venugopal et al. (Tue,) studied this question.