Exposure to ambient particulate matter air pollution, blood pressure and hypertension in children and adolescents: A national cross-sectional study in China

Background: Air pollution has been associated with elevated blood pressure in adults. However, epidemiological evidence from children and adolescents is limited. We investigated the associations between long-term exposure to particulate matter (PM)air pollution and blood pressure in a large population of children and adolescents. Methods: A cross-sectional analysis was performed in a nationally representative sample consisting of 43,745 children and adolescents aged 7 to 18 years in seven provinces in China. Exposure to ambient fine particles (PM _2.5 )and thoracic particles (PM ₁₀ )was estimated using spatiotemporal models based on satellite remote sensing, meteorological data and land use information. Mixed-effects (two-level)linear and logistic regression models were used to investigate the associations between PM exposure and systolic blood pressure (SBP), diastolic blood pressure (DBP)and hypertension. Results: After adjustment for a wide range of covariates, every 10 μg/m ³ increment in PM _2.5 and PM ₁₀ concentration was associated with 1.46 [95% confidence interval (CI): 0.05, 2.88]and 1.36 (95% CI: 0.34, 2.39)mmHg increases in SBP, respectively. PM ₁₀ was also associated with higher prevalence of hypertension [odds ratio per 10 μg/m ³ increment: 1.45 (95% CI: 1.07, 1.95)]. Conclusions: Long-term exposure to ambient PM air pollution was associated with increased blood pressure and higher prevalence of hypertension in children and adolescents. Our findings support air pollution reduction strategies as a prevention measure of childhood hypertension, a well-recognized risk factor of future cardiovascular health.