March 9 (HealthDay News) -- Women who use antidepressants appear to be at heightened risk for sudden cardiac death, although the exact nature of the link remains unclear, researchers say.
The finding doesn't necessarily mean that antidepressant drugs are dangerous, the researchers said.
"We suspect that their use is a marker for people with worse depression," explained study lead author Dr. William Whang, an assistant professor of clinical medicine at Columbia University Medical Center in New York City. "The elevated risk seems more specific for antidepressant use, but that use may well be a marker of more severe symptoms."
The link between depression and heart trouble is more likely physical than psychological, Whang added. "We found that women who had worse depressive symptoms had higher rates of risk factors such as hypertension, diabetes and smoking," he said.
Women with clinical depression were more than twice as likely to experience sudden cardiac death, the report said.
The findings were published in the March 17 issue of the Journal of the American College of Cardiology.
The researchers relied on data on more than 63,000 American women in the Nurses Health Study. And while the research team did find a link between depression and heart risk, the incidence of sudden cardiac death was associated more strongly with the use of antidepressant drugs than with symptoms of depression.
Antidepressant drug use was not associated with a higher risk of heart attacks or overall fatal heart disease, just with sudden cardiac death, the study found.
Previous studies have shown a link between depression and higher mortality for people who already had heart disease, Whang said. "But this was a group of women without heart disease, and that makes it different," he noted.
The results do not necessarily apply to men because only women were in the study, Whang said. "It's hard to make more generalized conclusions," he said.
But for doctors seeing women with depression, there is a clear message, Whang said.
"The biggest clinical implication is that management of coronary heart disease risk factors may be especially important for those with depressive symptoms," he said. "Taking care of those risk factors can modify the risk for coronary disease."
Dr. Sanjiv M. Narayan, an associate professor of medicine at the University of California, San Diego, School of Medicine and co-author of an accompanying editorial, said in a statement that the "data indicate the link between depression and serious heart rhythm problems may be more complex than previously thought."
His editorial called the relationship between antidepressant use and sudden cardiac death "surprising" and added it "merits scrutiny."
But it is possible that "antidepressant use merely indicates that depression is of sufficient severity to merit treatment," the editorial said. One recent study of people with heart failure found that depression was associated with increased mortality but that use of antidepressants was not.
Another report in the same issue of the journal said that feelings of anger and hostility are significantly associated with a higher risk of heart disease in healthy people and a poorer outcome in people with heart disease.
Anger and hostility predicted a 19 percent increased risk of such coronary heart disease events as heart attacks among healthy people, and a 24 percent increased risk among those with existing heart disease, said the report by researchers at University College, London.
The British study, which reviewed 42 studies, found the same relationship seen in the study of depression and heart disease: an increase in behavioral risk factors for coronary problems. A subset analysis found that the increased risk could be explained by such factors as smoking, physical activity and obesity, the report said.
SOURCES: William Whang, M.D., assistant professor, clinical medicine, Columbia University Medical Center, New York City; March 17, 2009, Journal of the American College of Cardiology