Fine particulate matter air pollution and subclinical cardiovascular outcomes: A longitudinal study in 15 Chinese...

Although previous studies have linked short-term exposure to fine particulate matter (PM_2.5) air pollution with various molecular biomarkers of cardiovascular system, limited evidence is available for indicators at clinical or subclinical levels. We examined the associations between short-term PM_2.5 exposure and a range of clinical or subclinical indicators of cardiovascular health in general population.

A longitudinal repeated-measure study was conducted among 247,640 participants who repeatedly visited health examination centers in 15 typical cities across China from 2013 to 2020. A total of 19 well-established indicators of cardiovascular risk or injury were evaluated and air quality data at nearest fixed-site monitors were collected. Linear mixed-effects models with distributed lag models were used to analyze the potentially lagged effects of PM_2.5. The average daily PM_2.5 concentration was 48 μg/m³ during the study period. PM_2.5 exposure was associated with significant changes of 16 indicators with the effects generally peaked on lag 0 to 3 day. For an interquartile range (IQR) elevation (37 μg/m³) in PM_2.5 concentrations over lag 0-7 day, the cumulative percentage changes were 0.50% to 1.27% in heart rates and blood pressure, 0.10% to 5.04% in inflammatory markers, -0.29% to 1.39% in blood viscosity parameters, -0.67% to 3.45% in blood lipids, 0.89% in blood homocysteine, 0.13% to 0.78% in myocardial enzymes, and 3.03% in pulse wave velocity. These associations were not substantially changed after adjusting concomitant exposures to gaseous pollutants.

Short-term exposure to PM_2.5 may induce early cardiovascular effects in general population, including acute inflammation, myocardial injury, increased blood viscosity, vascular stiffness and hyperlipidemia.