Residential Ambient Particulate Air Pollution and Blood Pressure in Peri-Urban India

摘要

Long-term exposure to ambient fine particulate matter (PM2.5) has been linked to high blood pressure in high-income countries. However, it is unclear if these findings are generalizable to low- and middle-income countries, which may have higher PM2.5 levels dominated by different and mixed sources. We examined cross-sectional associations between annual residential ambient PM2.5 and black carbon (BC) levels with systolic blood pressure (SBP) and diastolic blood pressure (DBP) in adults living in a peri-urban area outside of Hyderabad, India. Blood pressure was measured in the right arm after 5 minutes of sitting rest using an oscillometric device. Annual averages of PM2.5 and BC at residence were estimated using land-use regression models. Participants (N=5,531, 18-84 years, 54% men) lived in 2,296 households across 28 villages. We used nested linear mixed-effect models (households nested within villages) stratified by sex to estimate associations between within-village differences in PM2.5 or BC and SBP and DBP. Annual average PM2.5 was 32.8 μg/m3 (SD=2.7) and BC was 2.5 μg/m3 (SD=0.2). In women, SBP increased by 1.47 mm Hg (95%CI, 0.21 to 2.74) per 1 μg/m3 increase in PM2.5 after adjusting for personal, household, and environmental confounders. Results were weaker and not statistically significant in men, for DBP, and for BC (in both men and women). Adjustment for cooking fuel did not change the results. Our study provides support for an association between ambient PM2.5 and SBP in women, independently of the type of cooking fuel. Further research focusing on personal exposure and using longitudinal designs is needed to provide valuable insights into the relationship between particle exposure and blood pressure in populations exposed to relatively high ambient concentrations, such as those present across much of India.