Ambient coarse particulate matter and the right ventricle: The multi-ethnic study of atherosclerosis

BACKGROUND: Coarse particulate matter (PM_10–2.5) is primarily mechanically generated and includes crustal material, brake and tire wear, and biological particles. PM_10–2.5 is associated with pulmonary disease, which can lead to right ventricular (RV) dysfunction. Although RV characteristics have been associated with combustion-related pollutants, relationships with PM_10–2.5 remain unknown. OBJECTIVES: To quantify cross-sectional associations between RV dysfunction and PM_10–2.5 mass and components among older adults and susceptible populations. METHODS: We used baseline cardiac magnetic resonance images from 1,490 participants (45–84 y old) from the Multi-Ethnic Study of Atherosclerosis and assigned 5-y residential concentrations of PM_10–2.5 mass, copper, zinc, phosphorus, silicon, and endotoxin, using land-use regression models. We quantified associations with RV mass, end-diastolic volume, and ejection fraction after control for risk factors and copollutants using linear regression. We further examined personal susceptibility. RESULTS: We found positive associations of RV mass and, to a lesser extent, end diastolic volume with PM_10–2.5 mass among susceptible populations including smokers and persons with emphysema. After adjustment for copollutants, an interquartile range increase in PM_10–2.5 mass (2:2 μg/m³) was associated with 0:5 g (95% CI: 0.0, 1.0), 0:9 g (95% CI: 0.1, 1.7), and 1:4 g (95% CI: 0.4, 2.5) larger RV mass among former smokers, current smokers, and persons with emphysema, respectively. No associations were found with healthy individuals or with ejection fraction. CONCLUSIONS: Alterations to RV structure may represent a mechanism by which long-term PM_10–2.5 exposure increases risks for adverse respiratory and cardiovascular outcomes, especially among certain susceptible populations.