Long-term exposure to air pollution and incidence coronary and cerebrovascular events in the Rome Longitudinal Study

Background Although several studies found an association between air pollution exposure and mortality risk, especially for ischemic heart diseases (IHD), few studies have examined the effect on the incidence of coronary and cerebrovascular events. Aims We studied the association between long-term exposure to ambient air pollution at residence and the incidence of coronary events and stroke in a population-based cohort, the Rome Longitudinal Study (Cesaroni et al. EHP 2013). Methods The Rome Longitudinal Study includes 1,265,058 adults with 9 years of follow-up. Residential exposure to annual NO2 (by land use regression model) and PM2.5 (by Chemical Transport model) were available. We used Cox regression to evaluate the association between pollutants and incidence of coronary events and stroke (including fatal events, i.e. deaths within 28 days from the event), adjusting for several individual and contextual factors. Results A total of 38,377 and 27,825 subjects experienced incident coronary events and stroke, respectively. An increase of 10 ?g/m3 in NO2 was associated with a increased risk of coronary events (HR=1.02, 95% CI: 1.01-1.03). No association was found between NO2 and incidence of stroke. PM2.5 was not associated with incidence of both stroke and coronary events. However, residential exposure to both NO2 and PM2.5 was associated with an increased risk of fatal events. An increase of 10?g/m3 in NO2 was associated with fatal coronary events (HR=1.07, 95%CI: 1.04-1.09) and fatal stroke (HR=1.03, 95%CI: 1.00-1.07), and an increase of 10?g/m3 in PM2.5 was associated to both fatal coronary events (HR=1.15, 95%CI: 1.07-1.15) and fatal stroke (HR=1.15, 95%CI: 1.08-1.23). Conclusions This study showed an association between exposure to air pollution and incidence of coronary events and incidence of fatal coronary events and stroke.