Fine particulate matter constituents and sub-clinical outcomes of cardiovascular diseases: A multi-center study in China

Background: Limited evidence is available on the associations of long-term exposure to various fine particulate matter (PM2.5) constituents with sub-clinical outcomes of cardiovascular disease (CVD) in China. Objectives: We aimed to explore the associations of PM2.5 and its constituents with blood pressure (BP), fasting glucose, and cardiac electrophysiological (ECG) properties based on a national survey of 5852 Chinese adults, who participated in the Sub-Clinical Outcome of Polluted Air study, from July 2017 to March 2019. Methods: Annual residential exposure to PM2.5 and its constituents of each subject was predicted by a satellitebased mode. We assessed the associations between five main constituents [organic matter (OM), black carbon (BC), sulfate (SO42-), nitrate (NO3-), ammonium (NH4+)] of PM2.5 and systolic BP (SBP), diastolic BP (DBP), fasting glucose, and ECG measurements (PR, QRS, QT, and QTc interval) using multivariable linear regression models. Results: Long-termPM2.5 exposure was significantly associated with increased levels of fasting glucose, DBP, and ECG measurements. An IQR increase in OM (8.2 mu g/m(3)) showed considerably stronger associations with an elevated fasting glucose of 0.39 mmol/L (95%CI confidence interval: 0.28, 0.49) compared with other PM2.5 constituents. Meanwhile, an IQR increase in NO3-, NH4+ and OMhad stronger associationswith DBP and ECG parameters compared with BC and SO42-. Conclusions: This nationwide multi-center study in China indicated that some constituents (i.e., OM, NO3-, and NH4+) might be mainly responsible for the association of PM2.5 with sub-clinical outcomes of CVD including BP, fasting glucose, and ECG measurements. (C) 2020 Elsevier B.V. All rights reserved.