Aspirin: Low-Dose Gets High Marks for Heart Attack Prevention

From the WebMD Archives

Jan. 11, 2001 -- Taking as little as one baby aspirin a day can help ward off heart attacks in people at high risk for one, according to new research. The Italian investigators also looked to see what benefits vitamin E had on the heart -- and didn't find any.

While the jury is still out on vitamin E, experts tell WebMD that people concerned about heart disease should discuss taking aspirin with their physician.

A heart attack occurs when the heart muscle is damaged because its blood supply is cut off. This can be due to a blood clot blocking one of the heart's blood vessels or by a narrowing of these vessels, called atherosclerosis. According to 1997 statistics from the American Heart Association, more than 1 million new or recurrent cases of heart attack take place each year in the U.S. -- and more than 40% of victims die. One in every five deaths in the U.S. is caused by heart disease.

Because of its anticlotting properties, aspirin is sometimes used to prevent subsequent heart attacks in people who already have had one or in people who are otherwise at risk. Doctors are careful how much aspirin they recommend, however, as an infrequent but important side effect of taking aspirin is excessive bleeding that could lead to a stroke.

Vitamin E also has been used to ward off heart attacks. The theory is that vitamin E's antioxidant effects counteract the damage done when oxygen breaks down in the body -- thus helping to prevent the harm to blood vessels caused by atherosclerosis.

'"This research doesn't present anything terribly new, but it really clarifies areas that have been fuzzy in the past," says Walter W. Rosser, who wrote an editorial commentary on the study, both of which are published in this week's issue of the British medical journal The Lancet.

The study confirms that you should take a low-dose, rather than a high-dose aspirin tablet, Rosser tells WebMD. "You only need one 80-100 mg [tablet] a day," he says.

The study also tells us that people over age 50 with risk factors for heart disease are the ones who should take aspirin as a preventive therapy.


The study's final message is that "the risk of stroke [associated with taking aspirin] is directly linked to blood pressure. As long as blood pressure is well controlled ... then the risk of stroke [from taking aspirin] is quite low and the benefits of the aspirin [on the heart] overtake any risk of stroke." Rosser is a professor and chair of the department of family and community medicine at the University of Toronto in Ontario.

For the study, which received financial support from aspirin manufacturer Bayer Company, doctors examined almost 5,000 people with at least one risk factor for heart disease -- such as obesity, diabetes, high blood pressure, or high cholesterol. The volunteers were told to take 100 mg of aspirin a day and/or 300 mg of vitamin E a day, or neither of these.

After 3½ years, those taking aspirin were less likely to have suffered a heart attack or to have died of heart disease. Vitamin E did not produce such benefits. The study was led by Maria Carla Roncaglioni of the Instituto Di Richerche Farmacologiche in Milan, Italy.

Despite intense scientific interest in vitamin E's effect on the heart, recent studies, including this one, indicate it's not all that beneficial, Michael J. Ryan, MD, tells WebMD.

On the other hand, he says, for the prevention of heart attack, "I think aspirin is important." Ryan, who reviewed the study, is assistant professor of medicine at Thomas Jefferson University Hospital and director of the cardiovascular risk identification and treatment center at Main Line Health Heart Center, both in Philadelphia.

In contrast, Rosser says, "My sense with vitamin E is that it's likely that probably over a very long period of time it does have some effect, and 3½ years just isn't anywhere near long enough to show anything."

Both Rosser and Ryan agree that individuals concerned about heart disease should discuss taking aspirin with their physician.

"If you decide to take something for the rest of your life, even if it's plain old aspirin, that's a major decision," Rosser says. "Therefore, most people should talk to somebody that's knowledgeable about it -- and usually that's a physician."