Coarse Particulate Matter Exposure And Inflammation

Emilie Elizabeth Davis

This thesis is restricted to Yale network users only. It will be made publicly available on 08/28/2021

Abstract

Background

Cardiovascular disease (CVD) is the leading cause of death in the United States, and environmental exposures, such as air pollution, contribute to the risk of CVD. While previous studies have found that fine particles, PM 2.5, are associated with CVD risk, fewer studies have considered the effect of coarse particles, PM 10-2.5, on CVD risk and the possible biological mechanism through which this environmental exposure could increase CVD risk.

Methods

This analysis examines the association between ambient concentrations of PM 10-2.5 and a marker of CVD risk in a cohort of midlife women. Annual questionnaire and clinical data were obtained from women enrolled in the longitudinal Study of Women's Health Across the Nation (SWAN) at six study sites from 1999 to 2004, including repeated measurements of high-sensitivity C-reactive protein (hs-CRP). Residential locations and the US EPA air monitoring network measurements were used to assign exposure to PM 10-2.5, as well as PM 2.5, ozone, CO, NO2, and SO2, for exposure windows of 30 days, six months, and one year prior to annual clinic visits for each of the study participants. A linear mixed effects regression model was performed to describe the association between PM 10-2.5 exposure and serum levels of hs-CRP, including additional covariates.

Results

For the 1694 women included in this analysis, prior six months PM 10-2.5 exposure was associated with increased levels of hs-CRP after adjusting for study site, race/ethnicity, education, menopause status, body mass index (BMI), and active smoking status. A 5.7% increase in hs-CRP per 5 μg/ m3 increase in mean PM 10-2.5 was found for the six months exposure window. The association between prior six months PM 10-2.5 exposure and hs-CRP remained even when models included co-exposure to PM 2.5, CO, and NO2, respectively.

Conclusions

This analysis suggests that long-term exposure of PM 10-2.5 is associated with adverse effects on levels of hs-CRP, potentially increasing CVD risk in addition to traditional risk factors. Future studies should consider the clinical relevance of hs-CRP levels and exposure to PM 10-2.5 as well as improvements in exposure assessment approaches for PM 10-2.5.