Can traffic pollution lead to heart disease?

High levels of traffic pollution is linked to changes in the mass and size of the right chamber of the heart, which in turn can lead to heart disease, a study suggests.

In the report, published by the American Journal of Respiratory and Critical Care Medicine, lead author Dr. Peter Leary writes that right heart failure is known to be a cause of common and rare heart and lung diseases, as well as related deaths.

Leary, of the University of Washington Medical Center in Seattle, notes that previous studies have looked into already established links between traffic pollution and changes to the left ventricle, heart failure and death from cardiovascular diseases, but their connection with the right ventricle has not been studied in full.

"The morphologic changes in the right ventricle of the heart that we found with increased exposure to nitrogen dioxide add to the body of evidence supporting a connection between traffic-related air pollution and cardiovascular disease," Leary explained in a statement.

Leary and colleagues looked at 3,800 healthy participants with no signs of cardiovascular disease using MRIs. They compared their heart scans with those of people exposed to outdoor oxides of nitrogen, including nitrogen dioxide, in the 12 months leading up to the scans. The increased exposure to nitrogen dioxide was linked to a 5 percent increase in right ventricular mass and a 3 percent increase in right ventricular end-diastolic volume, or the volume of blood in the chamber at the end of filling.

The American Thoracic Society applaud this research, and say as physicians, they are concerned about their patient's ability, to breathe -some more than others.

"The effects of smog on respiratory health are particularly pronounced for patients living with asthma, COPD, or other lung diseases," President Dr. Patricia Finn said.

The authors note that the study does not prove that traffic pollution causes the observed changes, but the evidence leans in that direction.

"The many adverse effects of air pollution on human health support continued efforts to reduce this burden," Leary adds.