Fine particulate air pollution and premature atrial contractions: The REasons for Geographic And Racial Differences...

Several reports have suggested that particulate matter (PM) exposure increases the risk for atrial arrhythmias. However, data from large-scale epidemiologic studies supporting this hypothesis are lacking. We examined the association of PM <2.5 μm in diameter (PM_2.5) concentration with premature atrial contractions (PACs) in 26,609 (mean age=65±9.4 years; 55% female; 41% black) participants from the REGARDS (REasons for Geographic And Racial Differences in Stroke) study. Estimates of short- (2 weeks) and long-term (1 year) PM_2.5 exposure were computed before each participant's baseline visit using geographic information system data on the individual level at the coordinates of study participants' residences. PACs were identified from baseline electrocardiograms. A total of 2140 (8.2%) participants had evidence of PACs on the baseline electrocardiogram. Short-term PM_2.5 (per 10 μg/m³) exposure was not associated with PACs (OR=1.09, 95% CI=0.98, 1.23). Increases in long-term PM_2.5 (per 10 μg/m³) were associated with PACs (OR=1.40, 95% CI=1.10, 1.78). Interactions were not detected for short- and long-term PM_2.5 exposure by age, sex, or race. Long- but not short-term PM_2.5 exposure is associated with PACs. This suggests a role for long-term PM_2.5 exposure in initiating supraventricular arrhythmias that are triggered by PACs.