Associations of outdoor fine particulate air pollution and cardiovascular disease: Results from the Prospective Urban and Rural Epidemiology Study in China (PURE-China)

Abstract

BackgroundEvidence on whether an excess risk of incidence and mortality of cardiovascular disease (CVD) among people exposed to a high level of ambient PM2.5 in low- and middle-income countries (LMICs) is lacking. This study aimed to investigate the associations between long-term exposure to ambient fine particulate matter<2.5 µm (PM2.5) concentrations and the risk of incidence and mortality of CVD in a large cohort study from 115 communities. MethodsIn this cohort study, we followed 42 160 adults aged 35–75 years at baseline who enrolled in the Prospective Urban and Rural Epidemiology Study conducted in China (PURE-China) between 2005 and 2009 with ambient PM2.5 estimates, and followed up until August 2021. Cox proportional hazards frailty models were used to estimate the associations between long-term mean outdoor PM2.5 concentrations and CVD events, CVD mortality, and all-cause mortality. FindingsDuring a median follow-up period of 11.8 years, we documented 2 190 deaths, including 732 CVD deaths. There were 4 559 (10.8 %) of 42 160 participants who experienced incident total CVD, among them there were 861 myocardial infarctions (MI) and 2 338 S. The 3-year median concentration of ambient PM2.5 before the cohort commencement was 52.7 µg/m3 (interquartile range [IQR] 30.3–74.6). In full adjusted model, a 10 µg/m3 increase in PM2.5 was associated with a hazard ratio (HR) of 1.12 (95 % CI 1.11–1.14) for major CVD and 1.03 (95 % CI 1.01–1.05) for all-cause mortality. Besides, long-term PM2.5 concentrations had a significantly positive gradient association with total CVD and a similar pattern of associations with other CVD outcomes was observed. InterpretationThis study demonstrated that long-term ambient PM2.5 concentrations is positively associated with increased risks of CVD in adults aged 35–70 years from China. This finding reinforces the need for policymakers to adopt more effective strategies to improve air quality.