Why marriage might have this effect isn't clear. The researchers, however, suggest several possible reasons.
Single people may be more likely to be in poor health, they said. Married people may be better off financially, live healthier lives and have more friends and social support, all of which promotes health. Married people also may be more likely to call an ambulance sooner than single people, the researchers said.
In addition, married couples get better treatment in the hospital and after discharge, the researchers noted.
On the other hand, the researchers suggested, single people may be less likely to follow measures that might help prevent heart attacks -- such as taking daily aspirin, cholesterol-lowering statins and medications to control high blood pressure.
"For better or worse, marriage is associated with better cardiovascular health and a lower risk of death due to an acute coronary event," said Dr. Gregg Fonarow, a professor of cardiology at the University of California, Los Angeles.
The reasons marriage or cohabitation may protect people from heart attacks requires further study, he added. Further research is also needed to establish a cause-and-effect relationship between marital status and heart attack incidence and survival.
To learn more about heart attacks, visit the American Heart Association.
SOURCES: Aino Lammintausta, M.D., Turku University Hospital, Finland; Gregg Fonarow, M.D., professor of cardiology, University of California, Los Angeles; Jan. 31, 2013, European Journal of Preventive Cardiology
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