April 27, 2006 -- New research points to yet another issue we can blame on our mothers -- our risk of heart diseaseheart disease.

The risk of coronary heart disease passed from mothers is greater than the risk from fathers, and risk is even greater if both parents have heart disease, according to study results slated to be published in the June issue of the American Journal of Preventive Medicine. The findings were presented Thursday at a media briefing on cardiovascular disease sponsored by the American Medical Association in New York City.

While it is well known that family history of heart disease is an independent risk factor for heart attackheart attack and strokestroke, until now little was known about how the sex of the affected parent influenced this risk.

Moms' Habits

Exactly why the risk from mothers is greater than the risk from fathers is not fully understood. Genetic factors may play a role, suggests Kristina Sundquist, MD, PhD. Sundquist is an assistant researcher at the Karolinska Institute's Center for Family Medicine in Stockholm.

Another possible factor, says Sundquist, is that kids tend to spend more time with their moms. As a result they are more likely to pick up their mother's bad habits.

"If moms with heart disease are more likely to smoke, be physically inactive, or have a poor diet, this can influence behavior in their offspring and influence heart disease risk," she says. The findings may call for "mother-child oriented long-term prevention of coronary heart disease with a focus on behavioral [issues]."

Moms vs. Dads

Sons had a 41% greater risk of developing heart diseaseheart disease if their dads had heart disease and a 55% greater risk if their moms did, the study shows. Daughters had a 17% increased risk of developing heart disease if their dads had a history of heart disease and a 43% increased risk if their moms did.

Children with two parents with heart disease had an 82% increased risk of developing it themselves, the study shows. What's more, children whose parents developed heart disease at an early age (before they turned 55) had a 300% greater risk of developing the disease.

"Of course, clinical attention should be given to patients whose mothers or fathers had heart disease, and special attention should be given to patients if both their parents had heart disease, their mother had heart disease, or if the [parent's] onset was at an early age," she says.

Comparing Parental Histories

To arrive at their findings, Sundquist and colleagues used data linked from different Swedish registries. The first database came from Swedish men and women born since 1932. This was linked to information about their parents -- as well as coronary heart disease -- and then to hospital admissions and deaths.

The database included 10,496 men and 3,281 women who had a mother and/or a father with heart disease. They then compared people with heart disease whose parents also had it to patients with heart disease but without parental history.

Calling the new research "exciting data," Sharonne N. Hayes, MD, director of the Women's Heart Clinic at the Mayo Clinic in Rochester, Minn., says that the findings underscore the importance of family history as a risk factor for heart disease. "This type of information about the strength of family history can help us understand why knowing our family history is so important."

SOURCES: Kristina Sundquist, MD, PhD, assistant professor, Karolinska Institute's Center for Family Medicine, Stockholm, Sweden. Sharonne N. Hayes, MD, director, Women's Heart Clinic, Mayo Clinic, Rochester, Minn.; associate professor of medicine and cardiovascular disease, Mayo Clinic College of Medicine, Rochester, Minn. Sundquist, K. American Journal of Preventive Medicine, 2006 (in press).