Taking antidepressants may raise the risk of heart disease in men by producing a thickening of artery walls, researchers said Saturday. Although a potential mechanism for the action is not obvious, the drugs appear to accelerate atherosclerosis by increasing the thickness of what is known as the intima media, the inner and middle layers of the arteries, particularly the carotid arteries that feed blood to the brain, researchers from Emory University in Atlanta reported at a New Orleans meeting of the American College of Cardiology.
Dr. Amit Shah, a cardiology fellow at Emory, and his colleagues studied 513 male twins, with a mean age of 55, who were part of the Vietnam Era Twin Registry. Overall, when the researchers adjusted for age, diabetes, blood pressure and other factors, they found that the intima-media thickness of men taking antidepressants was 37 microns (about 5%) thicker than that of men not taking the drugs. When the team looked at 59 twin pairs in which one twin was taking the drugs and the second was not, the artery was 41 microns thicker in the twin taking the drugs.
Previous studies have shown that depression itself is not linked to an increased intima-media thickness, neither is post-traumatic stress disorder. Intima-media thickness normally increases by about 10 microns per year as a man ages, so the twin taking antidepressants was physically four years older than his brother -- at least in terms of his artery health, Shah said. Previous studies have also shown that each 10-micron increase in thickness is associated with a 1.8% increase in risk of cardiovascular disease, so that a 40-micron increase in thickness produces a 7.2% increase in risk.
Experts cautioned that the link does not necessarily imply a cause-and-effect relationship, particularly because no clear-cut biological mechanism is postulated. Men taking the drugs should continue taking them, they added, because the effects of depression could be more disabling then the increased risk of heart disease.