"This data is very consistent with reports that this kind of exposure leads to inflammation, cholesterol build-up in the arteries and heart attacks, although there's also a lot of data about stress and its connections to heart attacks," said Dr. Gregg C. Fonarow, a professor of cardiology at the University of California, Los Angeles. "So, probably both of these factors are working synergistically to raise the cardiovascular risk."
For his part, Dr. Bertram Pitt, a professor of medicine emeritus at the University of Michigan School of Medicine in Ann Arbor, agrees "there's enough basic evidence to suggest that air pollution of this kind increases oxidative stress, and could lead to vascular trauma."
"So I'm not surprised by this finding at all," added Pitt. "It's very plausible and very worthy of further exploration."
"But," noted Fonarow, " I think it's important to keep in perspective that although the relative risk for heart attack was high following traffic exposure, the absolute risk was actually very, very small. Meaning, that given the number of times individuals are exposed to traffic and do not have heart attacks, these findings should not alarm the average person, because in absolute terms, the risk that being exposed to traffic every day will provoke a heart attack is exceptionally low."
For more on heart disease risk and air pollution, visit the American Heart Association.
SOURCES: Annette Peters, head, research unit, Institute of Epidemiology, Helmholtz Zentrum Munchen, Germany, and adjunct associate professor, Harvard School of Public Health, Boston; Gregg C. Fonarow, M.D., professor, cardiology, University of California, Los Angeles; Bertram Pitt, M.D., professor, medicine emeritus, University of Michigan School of Medicine, Ann Arbor; March 12, 2009, presentation, American Heart Association's Cardiovascular Disease Epidemiology and Prevention annual conference, Palm Harbor, Fla.