The study, which examined the air quality on a total of 37,000 days in nine separate cities, found that risk of hospitalization for ischemic stroke was one percent higher on days with relatively high levels of air pollution, compared with low-air pollution days, according to lead author Gregory Wellenius, Sc.D., postdoctoral fellow in cardiology at BIDMC.
"Although these effects sound relatively small, given the large number of people exposed to air pollution and the large number of people at risk for stroke, from a public-health perspective the actual number of strokes [we're talking about] could be significant," says Wellenius. Stroke is the third leading cause of death in the U.S., affecting more than 700,000 individuals each year.
Previous work by Wellenius and coauthors Murray Mittleman, MD, DrPH, of BIDMC's Cardiovascular Epidemiology Research Unit and Joel Schwartz, PhD, of HSPH had established a "consistent increased risk" for cardiac health problems associated with exposure to ambient air particles.
"Air pollution has been shown to trigger heart attacks and to aggravate the conditions of patients with congestive heart failure," says Mittleman, who is also Associate Professor of Medicine at Harvard Medical School. "These new findings, demonstrating that incidence of clot-based strokes also increase, is in keeping with our earlier data showing a relationship between air pollution and heart and lung disorders."
(The study also looked at the incidence of hemorrhagic stroke, which is caused by bleedi
Contact: Bonnie Prescott
Beth Israel Deaconess Medical Center