New US research has found that being married may have a protective effect for patients who have suspected or confirmed heart disease, with those who are unmarried, divorced, or widowed all at a higher risk of death than married patients.

Led by Arshed Quyyumi, M.D., co-director of Emory Clinical Cardiovascular Research Institute and professor of medicine at Emory University in Atlanta, the study looked at 6,051 patients with an average age of 63 who were undergoing cardiac catheterization for coronary artery disease.

Although it is already known that those who are divorced have an increased risk of death in general, few studies have looked at the relationship between adverse cardiovascular outcomes and marital status in patients who already have known or suspected cardiovascular disease.

For the new study the team assessed marital status using questionnaires and followed the patients for a median of 3.7 years.

The team found that compared to married patients, those who were unmarried had a 24 percent higher risk of death from any cause, a 45 percent higher risk of death from cardiovascular disease, and a 52 percent higher risk of cardiovascular death/heart attack.

The team also found that those who were unmarried, a higher proportion of whom who were female and black, had hypertension, heart failure, or high cholesterol and less likely to be smokers compared with the married patients.

In addition, the risk of cardiovascular death or heart attack was 40 percent higher for those who were never married, 41 percent higher for those who were divorced or separated, 71 percent higher for those who had been widowed.

"I was somewhat surprised by the magnitude of the influence of being married (on heart patients)," said Quyyumi. "Social support provided by marriage, and perhaps many other benefits of companionship, are important for people with heart disease."

The team now suggest that health professions should take into consideration marital status when treating patients with coronary artery disease.

However, they also noted that the findings cannot be applied to the general population without cardiovascular disease, and the study also did not look at patients who cohabited.

The results can be found published in Journal of the American Heart Association, the Open Access Journal of the American Heart Association/American Stroke Association.