Heatwave Exposure and Hypertension Among Rural Adults in Banaskantha District, Gujarat, India: A Community-Based Cross-Sectional Epidemiological Study

Background Rising ambient temperatures and recurrent heatwaves represent an emerging environmental risk factor for cardiovascular disease, particularly in rural populations with high occupational heat exposure. Evidence linking chronic heat exposure to hypertension in rural India remains limited. Methods A community-based cross-sectional study was conducted between 2019 and 2025 in Banaskantha district, Gujarat, India. Adults aged 18–70 years with ≥ 5 years of residence were recruited from rural talukas with varying heat exposure intensity (Moriya, Vav, Tharad, and other rural regions). Blood pressure was measured using standardized automated sphygmomanometers. Hypertension was defined as systolic blood pressure ≥ 140 mmHg, diastolic blood pressure ≥ 90 mmHg, or current antihypertensive treatment. Environmental heat exposure was classified using district-level meteorological records based on long-term temperature patterns and heatwave frequency. Descriptive statistics and exploratory multivariable linear regression analyses were performed. Results A total of 300 participants were included (Moriya n = 120; Vav n = 70; Tharad n = 60; other talukas n = 50). Overall hypertension prevalence was 49.7%. Mean systolic blood pressure was highest in Moriya (166 ± 19 mmHg), followed by Vav (158 ± 17 mmHg), Tharad (154 ± 16 mmHg), and other talukas (150 ± 15 mmHg). A graded increase in systolic blood pressure was observed across increasing environmental heat exposure categories. After adjustment for age and sex, residence in high heat-exposure talukas was independently associated with higher systolic blood pressure (adjusted β = +12.8 mmHg; p < 0.001). Conclusions Hypertension prevalence was high among rural adults residing in heat-exposed regions of Banaskantha district. Exploratory findings suggest a significant association between chronic heatwave exposure and elevated blood pressure. Longitudinal studies are required to further quantify cardiovascular risk in climate-vulnerable rural populations.