March 13 (HealthDay News) -- Burning buildings might not be the only risks that firefighters face. They also appear to be more likely than their peers in other professions to have prematurely narrowed arteries, increasing their risk for strokes and heart attacks, according to a new study.
In fact, 22 percent of a group of 77 firefighters studied by researchers at the University of Kansas averaged 39 years old but had the blood vessels of 52-year-olds because of significant plaque buildup in their carotid arteries.
"These men, as young as they are, for some reason have a high rate of early development of vascular disease, asymptomatic as it is," said Dr. Patrick Moriarty, director of the Atherosclerosis and LDL Apheresis Center at the University of Kansas Medical Center and the study's lead researcher. "What it means is that we have to find a way to make their job have less risk potential in terms of less cardiovascular risk."
The findings were presented March 12 at the American Heart Association's conference on cardiovascular disease in Palm Harbor, Fla.
The demands of firefighters' jobs and their health needs often conflict, Moriarty explained. The stress of being on call for 48 hours, for instance, takes a toll on the body, he said. And, in addition, firefighters need high-calorie meals because, if they have to quickly leave to fight a fire, they might not have another meal for 24 hours, Moriarty said.
Dr. Gregg C. Fonarow, a professor of medicine and associate chief of the cardiology division at the University of California, Los Angeles, said that exposure to small particulate matter in smoke that occurs at fires also is harmful. Smoke, he said, provokes inflammation, which is associated with heart disease and stroke.
Also, many firefighters sleep during the day and work at night, which might be a problem because "there is some data about night workers having premature atherosclerotic events," Fonarow said. Atherosclerosis occurs when cardiovascular arteries thicken and the space for blood flow narrows.
Moriarty said that his interest in the cardiovascular risks for firefighters stemmed from having treated a number of them at clinic. Background information in his study noted that cardiovascular disease has been associated with 45 percent of the on-duty deaths of firefighters in the United States, compared with 36 percent for other lines of work. The National Institute for Occupational Safety and Health has reported that sudden cardiac deaths are the leading cause of death in the line of duty for firefighters.
For the study, Moriarty's research team used sonography to measure lipid levels in the firefighters' carotid arteries. The study described the 77 firefighters as young, with a low prevalence of cardiovascular disease and the risk factors associated with it. But, they had "more advanced atherosclerosis than a non-firefighting population of similar age gender and race," the researchers wrote.
Fonarow said that he would like to see the study replicated by another lab with a similar group of firefighters. The 13-year difference between the average chronological age of the group and the average age of the carotid arteries is large, he said, and could have important consequences for cardiovascular health.
When there is only a 10-year difference, there is a substantial risk of cardiovascular events, Fonarow said, and "the risk of heart attack and stroke rises substantially with each additional 10 years of life."
On the Web
The U.S. National Heart, Lung, and Blood Institute has more on atherosclerosis.
SOURCES: Gregg Fonarow, M.D., professor of medicine, and associate chief, division of cardiology, David Geffen School of Medicine, University of California, Los Angeles; Patrick M. Moriarty, M.D., director, Atherosclerosis and LDL Apheresis Center, University of Kansas Medical Center, Kansas City, Kan.; presentation, American Heart Association's Cardiovascular Disease Epidemiology and Prevention annual conference, March 12, 2009, Palm Harbor, Fla.