Long-Term Effects of Ambient PM2.5 on Hypertension and Blood Pressure and Attributable Risk Among Older Chinese Adults.

Long-term exposure to ambient fine particulate pollution (PM2.5) has been associated with cardiovascular diseases. Hypertension, a major risk factor for cardiovascular diseases, has also been hypothesized to be linked to PM2.5 However, epidemiological evidence has been mixed. We examined long-term association between ambient PM2.5 and hypertension and blood pressure. We interviewed 12 665 participants aged 50 years and older and measured their blood pressures. Annual average PM2.5 concentrations were estimated for each community using satellite data. We applied 2-level logistic regression models to examine the associations and estimated hypertension burden attributable to ambient PM2.5 For each 10 μg/m3 increase in ambient PM2.5, the adjusted odds ratio of hypertension was 1.14 (95% confidence interval, 1.07-1.22). Stratified analyses found that overweight and obesity could enhance the association, and consumption of fruit was associated with lower risk. We further estimated that 11.75% (95% confidence interval, 5.82%-18.53%) of the hypertension cases (corresponding to 914, 95% confidence interval, 453-1442 cases) could be attributable to ambient PM2.5 in the study population. Findings suggest that long-term exposure to ambient PM2.5 might be an important risk factor of hypertension and is responsible for significant hypertension burden in adults in China. A higher consumption of fruit may mitigate, whereas overweight and obesity could enhance this effect.