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Study finds new risk factor for stroke and heart attack
risk factors for stroke and heart attack have identified antibodies that
seem to double the risk of both health problems in men, independent of
other risk factors. Their study, published in the August issue of Stroke,
is the first prospective study to show increased risk of ischemic stroke
and heart attack among men with these particular antibodies, known as
Beta-2 Dependent Anticardiolipin Antibodies (B2GP1-dependent aCL).
Robin L. Brey, M.D., associate professor of medicine at The University
of Texas Health Science Center at San Antonio, said this study will help
researchers determine whether people with these antibodies should be treated
differently after they have a heart attack or a stroke.
"Now that we have proof that these antibodies are markers for increased
risk, we can turn our attention to how they are associated with stroke
and heart attack. We need to explore whether these antibodies cause stroke
or heart attack, and try to better understand the mechanism, if they are
found to be causative," said Dr. Brey, the study's lead author.
"The next step will be to use information about mechanism to develop
better strategies to decrease stroke and heart attack risk for people
with these antibodies," she said.
The 20-year study of men from Japanese ancestry showed that men with the
antibodies had a twofold increased risk of stroke, and a nearly double
increased risk of heart attack, when adjusted for other risk factors.
"Our study found that the risk of stroke and heart attack associated
with these antibodies was similar to the increased risk from other conditions,
such as hypertension and diabetes," said Steven J. Kittner, M.D.,
M.P.H., professor of neurology at the University of Maryland School of
Medicine and a neurologist at the Baltimore VA Medical Center. Dr. Kittner
is the study's senior author.
While it is clear that uncontrolled hypertension, diabetes, high cholesterol
and smoking increase the risk of cardiovascular disease, the researchers
say they do not know all of the predisposing risk factors. Many people
who suffer from a stroke or heart attack did not seem to be at high risk
based on the known factors.
Our bodies form antibodies after they are exposed to infection. The role
of inflammation and infection in cardiovascular disease is a major focus
of research, as part of the effort to better prevent, predict and treat
heart disease and stroke.
The B2GP1-dependent aCL antibodies were found in about 12 percent of men
in the study who did not have cardiovascular disease, but they were prevalent
in 17 percent of men who had a stroke and 16 percent of those who had
a heart attack. Scientists do not know which type of infection, if there
is one, may be responsible for these particular antibodies.
Contact: Aileen Salinas or Will Sansom