Household Air Pollution, Ambient PM2.5 and Hypertension: Baseline Data from a Chinese Cohort Study

摘要

Few previous studies adequately considered the influences of household air pollution from various heating sources when investigating the association between hypertension and outdoor fine particulate matter (PM2.5). This study aims to address this identified research gap using baseline data collected from PURE-China. A total of 45108 participants aged 35 to 70 were recruited from 2005 to 2009. We estimate ambient PM2.5 concentration according to participants' household location. Household air pollution referred to the utilities of different primary heating sources during the cold or rainy season. Hypertension was defined as self-reported physician diagnosed or receiving BP treatment or the measurement of DBP ≥ 90 mmHg or SBP ≥140mmHg at the interview. Multivariate logistic regression analyses were conducted to estimate the odds ratio and 95%CI with each 10ug/m3 increment of PM2.5, after adjusting potential confounding factors. Further analyses were carried out according to three levels of household air pollution (i.e., unclean, clean, never using heating fuels). With each 10μg/m3 increment of PM2.5, the OR for hypertension prevalence was 1.03(95%CI=1.04-1.14) according to the base model (i.e., adjustment of age, sex and region). After further including social economic status and disease history into the base model, the OR was 1.04(95%CI=1.02-1.06), and the effect retained almost unchanged if the household air pollution was included. Habitual use of unclean heating fuels significantly increased the risk of hypertension prevalence (OR=1.62,95%CI=1.49-1.76, vs. clean ones). No excess risk was observed for those using the clean heating source (OR=0.96, 95%CI=0.86-1.07 vs. never using heating fuels). This study highlights that both outdoor PM2.5 and emissions from using heating fuels indoors are significant associated with increased risk of hypertension. There is a pressing need for global actions on removal the source of air pollution via particularly engineering control.