Neighborhood sociodemographic effects on the associations between long-term PM exposure and cardiovascular outcomes and diabetes.

INTRODUCTION

Exposure to PM air pollution and neighborhood-level sociodemographic characteristics are associated with cardiovascular disease and possibly diabetes. However, the joint effect of sociodemographics and PM on these outcomes is uncertain.

METHODS

We examined whether clusters of sociodemographic characteristics modified effects of long-term PM exposure on coronary artery disease (CAD), myocardial infarction (MI), hypertension, and diabetes. We used medical records data from 2192 cardiac catheterization patients residing in North Carolina and assigned to one of six previously-determined clusters. For each participant, we estimated annual PM exposure at their primary residence using a hybrid model with a 1 km resolution. We used logistic regression models adjusted for age, sex, body mass index, and smoking status, to assess cluster-specific associations with PM and to determine if there were interactions between cluster and PM on outcomes.

RESULTS

Compared to cluster 3 (OR 0.93, 95% CI 0.82-1.07; urban, low proportion of black individuals and high socioeconomic status), we observed greater associations between PM and hypertension in clusters 1 (OR 1.22, 95% CI 0.99-1.50, p 0.03) and 2 (OR 1.64, 95% CI 1.16-2.32, p 0.003), which were urban, high proportion of black individuals, and low socioeconomic status. PM was associated with MI (OR 1.29, 95% CI 1.16-1.42) but not diabetes, regardless of cluster and was associated with CAD in cluster 3 (OR 1.15, 95% CI 1.00, 1.31) and overall (OR 1.07, 95% CI 0.98, 1.17).

DISCUSSION

Areas of relative disadvantage have a stronger association between PM and hypertension compared to areas of relative advantage.