Polluted Air Affects Heart Physiology

A number of previous studies warn of long-term ill effects of air pollution on human health.  Peter Leary, MD, MS, from the University of Washington Medical Center (Washington, USA), and colleagues analyzed data collected on 3,896 men and women, who did not have clinical cardiovascular disease, enrolled in the Multi-Ethnic Study of Atherosclerosis and who underwent cardiac magnetic resonance imaging (MRI).   Exposure to nitrogen dioxide served as a surrogate for exposure to traffic-related air pollution.  Using estimated exposure to outdoor oxides of nitrogen at the homes of participants over the year preceding MRI, the researchers found that increased exposure to nitrogen dioxide was associated with an approximately 1.0 g (5% ) increase in right ventricular mass and a 4.1 mL (3%) increase in right ventricular end-diastolic volume.  These relationships remained after accounting for differences among participants in cardiovascular risk factors, left ventricular mass and volume, markers of inflammation, lung disease and socioeconomic status.  Writing that: “Higher levels of [traffic-related air pollution] exposure were associated with greater [right ventricle] mass and larger [right ventricle] end-diastolic volume,” the study authors warn that such changes may associate with an increased risk for heart failure and cardiovascular death.