MONDAY, Oct. 15, 2001 (HealthDayNews) -- A new study supports the theory that one kind of antidepressant drug can help prevent heart disease not only by relieving the burden of depression but also by preventing blood clots, say researchers.
There is still a long way to go to prove that theory, says study leader Dr. Stephen E. Kimmel, assistant professor of medicine and epidemiology at the University of Pennsylvania in Philadelphia. But he says the study did find a 65 percent lower risk of heart attack in persons taking the class of antidepressants called selective serotonin reuptake inhibitors (SSRIs).
The finding appears in the Oct. 16 issue of Circulation: Journal of the American Heart Association.
"We don't know if what we are seeing is an effect of treating depression itself or some pharmaceutical effect. Our theory is that it is a pharmaceutical effect," Kimmel says.
Depression is a known risk factor for heart disease and for an increased risk of dying after a heart attack, and treating depression can reduce those risks, Kimmel says. The idea that SSRIs might have a different effect stems from several recent studies showing that they prevent blood components called platelets from clumping to form blood clots, he says.
"The basic science behind [this] is that they do have effects on platelets that might inhibit clotting," Kimmel says.
He sought proof for that belief in data from a study originally designed to test the value of nicotine patches in preventing heart attacks. That study compared 653 smokers in the Philadelphia area who were hospitalized for heart attacks with 2,990 smokers who had not had heart attacks. The 65 percent reduced risk was found in the 143 patients taking SSRIs.
Kimmel says more studies are needed, especially because of the small number of persons in the new study. "First we have to confirm our finding in a randomized trial of smokers. Then we have to do a study in nonsmokers, and a study to see if this is an effect of SSRIs themselves or of antidepressants in general."
Kimmel says his group is making preliminary plans for such studies. "Hopefully, other people will work on them as well," he says. The ideal would be one large-scale study including smokers and nonsmokers, which "would settle all those questions at once," he says.
SSRIs are named because they act on serotonin, a chemical that carries signals between nerve cells. They include fluoxetine, marketed as Prozac, fluvoxamine (brand name Luvox), paroxetine (Paxil), and sertraline (Zoloft). Other classes of antidepressants are the tricyclics and the monoamine oxidase (MAO) inhibitors, which have different molecular mechanisms.
Dr. Alan D. Michelson, director of the Center for Platelet Function Studies at the University of Massachusetts, says the institute is not currently doing research on the interaction of antidepressants and platelets, although research is going on elsewhere.
What To Do
"We are not recommending at this time that anyone should take an antidepressant to prevent heart disease," Kimmel says.
The University of Southern California provides basic information about antidepressants. The American Heart Association has a primer on heart attacks.
