TUESDAY, July 26 (HealthDay News) -- Genetics may play more of a
role in heart attacks than in strokes, a new British study
"A family history of heart attack appears to be a stronger risk factor for heart attack than a family history of stroke is for stroke," said study author Amitava Banerjee, a clinical lecturer in cardiovascular medicine at the University of Birmingham in England.
The findings should alter the way doctors predict a patient's
risk of heart attack and stroke based on family history, the
researchers said. And, "genes and genome-wide association studies
may not be critical to the field of stroke research," Banerjee
Both stroke and heart attack are leading killers of adults in
the United States.
For their report, published in the August issue of
Circulation: Cardiovascular Genetics, Banerjee's team collected data from the Oxford Vascular Study on 906 people who had heart attacks and 1,015 stroke survivors.
Among those with heart disease, 30 percent had a parent with a
heart attack and 21 percent had a sibling with a heart attack, the
Seven percent had two or more siblings who suffered heart
attacks, and 5 percent reported both parents had had heart
On the other hand, 21 percent of those who suffered a stroke or
transient ischemic attack, considered a minor stroke, had at least
one parent with a stroke, and 8 percent had a brother or sister
with a stroke.
Two percent of the stroke survivors had two parents with
strokes, while 14 percent had at least two siblings with a stroke,
the researchers found.
When two parents had suffered a heart attack, the risk of heart
attack increased six times. If one parent suffered a heart attack,
the risk was 1.5 times greater for their offspring.
Stroke risk did not change substantially based on parental
stroke history, the authors said.
The researchers reported that the risk of siblings developing
heart problems was similar among those with heart attack or
"Risk prediction models using family history currently lump a patient's family history of stroke and heart attack together," Banerjee said. "We probably should model family history of stroke and heart attack separately in the future."
Dr. Larry B. Goldstein, director of the Duke University Stroke
Center in Durham, N.C., said both heart attack and stroke are
associated with inheritable factors, but the mechanism of a heart
attack is usually the result of atherosclerosis, a hardening and
narrowing of the arteries.
"In contrast, stroke can occur through a variety of mechanisms," he said. "Therefore, it is not entirely surprising that having a family history of myocardial infarction [heart attack] would be a stronger risk factor for having a heart attack as compared to the relationship between having a family history of stroke and stroke risk."
However, based on other studies, family history remains an
important risk factor for stroke, and people who have a parent or
sibling who have had a stroke, particularly at a young age, should
take steps to reduce their risk, Goldstein said.
Dr. Gregg C. Fonarow, a professor of cardiology at the
University of California, Los Angeles, added that both heart
disease and stroke are to a great extent influenced by age,
modifiable risk factors and lifestyle, in addition to genetics.
People should recognize that a family history of heart disease
can be important information about future risk of having a heart
attack, Fonarow said. "However, the absence of family history in
and of itself should not be reassuring that one is at low risk for
cardiovascular disease," he stressed.
For more information on heart disease and stroke, visit the