Aspirin has been found for the first time to reduce the chances of heart attack among men who have the most common form of chest pain.

A five-year study involving 333 doctors who had chronic stable angina found those who took one aspirin every other day were 87 percent less likely to have heart attacks than those who did not."Our data indicated that alternate-day aspirin therapy greatly reduced the risk for (heart attacks) among patients with chronic stable angina, a group of patients at high risk for cardiovascular death," the researchers wrote in the Annals of Internal Medicine.

About 3 million Americans have angina. Angina is chest pain caused by arteries that have become narrowed by cholesterol buildup, boosting the risk for a heart attack. Most have the form known as chronic stable angina.

The new study was conducted by Dr. Charles Hennekens and his colleagues at the Brigham and Women's Hospital in Boston who run the Physicians' Health Study, an ongoing study of male health involving 22,071 male doctors nationwide.

The same study produced a landmark paper in 1988 that found men who took one aspirin every other day were nearly half as likely to experience their first heart attacks.