(HealthDay) -- People with a parent or sibling who died young from heart disease have a much higher risk of developing early heart disease themselves, a new Danish study indicates.
Death of a first-degree relative from cardiovascular causes before age 50 appears to double your risk of heart disease. If the deceased had not reached 35, that risk rises as much as tenfold, the researchers report.
"Cardiovascular death in a relative less than 50 years of age is a powerful risk factor for early onset cardiovascular disease in younger family members, particularly when there are multiple early cardiovascular deaths in a family and/or when cardiovascular deaths occur in very young persons," said lead researcher Mattis Flyvholm Ranthe, from the department of epidemiology research at the Statens Serum Institute in Copenhagen.
For the study, Ranthe's team collected data on the nearly 4 million Danes born between 1950 and 2008 and looked at family history of death before age 60, particularly from cardiovascular causes.
Nearly 258,000 premature deaths among relatives were identified. The researchers then discovered that 130,000 of the men and women in the study had heart disease by age 50, more than 31,000 had blocked heart arteries and more than 5,000 had abnormal heart rhythms.
The more early deaths there were in a family and the younger those relatives were when they died, the greater the risk of early onset cardiovascular disease, they found.
"The risk of early onset cardiovascular disease in persons whose relatives were less than 35 years of age when they died increased up to tenfold, while having two or more early deaths in the family increases risk of early-onset cardiovascular disease up to sixfold," Ranthe said. "Overall, death in a young relative -- less than 50 years of age at death -- due to cardiovascular causes doubles the risk of early-onset cardiovascular disease."
These findings suggest family history of early death from cardiovascular disease should receive more weight when evaluating people younger than 60 for heart disease risk, he said.
The findings -- which found an association but not a cause-and-effect relationship between a relative's early death and heart disease risk -- were published online Aug. 20 in the Journal of the American College of Cardiology.
Dr. Gregg Fonarow, a spokesman for the American Heart Association and a professor of cardiology at the University of California, Los Angeles, said "prior studies have shown that a family history of coronary artery disease or heart attack is associated with increased risk for cardiovascular events."
This is not to say that everyone whose close relative died prematurely of heart trouble is doomed to an early demise.
Careful documentation of a family history of premature cardiovascular death, together with assessment of traditional risk factors, could help identify people who would substantially benefit from intensified cardiovascular prevention efforts, he said.
"Individuals with a family history of premature cardiovascular death can, with appropriate preventive measures, change their fate," Fonarow said.
These measures include controlling blood pressure and cholesterol, maintaining normal weight, eating a healthy diet and getting regular exercise.
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More information: For more on heart disease, visit the American Heart Association.