Aspirin Therapy: Right for Your Heart?

Daily aspirin helps many, but age, gender, and heart disease risks play a part. Is it right for you?

Medically Reviewed by Brunilda Nazario, MD
From the WebMD Archives

Sandra Rose, a nurse in Raleigh, NC, started taking a daily aspirin because "it seemed like a wonder drug," preventing heart attacks and strokes. "All the patients seemed to be on a low-dose aspirin," 63-year-old Rose says. She started taking one herself.

Then, after hearing reports of stomach bleeding caused by aspirin, this wonder drug had Rose wondering: How can you tell if a daily aspirin is right for you?

Cardiovascular Disease and Aspirin Therapy

Heart attacks and strokes cause almost a million deaths every year in the U.S. The culprits are blood clots, which choke off the blood supply to vital organs. Aspirin works on blood cells that cause clots (platelets), making blood less likely to clot.

So if clots cause cardiovascular disease, and aspirin helps prevents clots, taking aspirin should be a no-brainer, right?

Not so fast. Aspirin's benefit comes at a cost -- an increased risk of bleeding, which usually occurs in the stomach, intestine and other gastrointestinal areas. While most of this type of bleeding is minor and stops on its own, it can be life-threatening. And there's no sure way to predict if or when it will happen.

"No medicine is innocuous," says Terry Jacobson, MD, director of the Office of Health Promotion and Disease Prevention at Emory University in Atlanta. "Anyone who's not at a high risk of heart disease has to weigh the benefits against the risks."

The right time to take aspirin is when the benefits -- reducing risk from heart attacks and strokes -- outweigh the risk of aspirin itself: dangerous stomach bleeding. This is a decision that can only be made between you and your doctor, but learning your own risk level can help you feel good about your choice.

Your Heart Disease Risk and Aspirin Therapy

There's little question aspirin has earned its reputation as a powerful drug. Studies comparing aspirin with placebo including almost 100,000 apparently healthy men and women showed:

  • In men, daily aspirin therapy cut the risk of a first heart attack by a third.
  • In women, daily aspirin therapy reduced the rate of strokes by 17%.

Certain conditions increase the likelihood of heart attacks and strokes. If you fit in this category, there's little argument: an aspirin a day helps keep trouble away.

High Risk Men and Women Who May Want Aspirin Therapy

You're considered at high risk if you have:

"For people with known heart disease, it's clear that they benefit from being on an aspirin," says Jacobson, yet "people shouldn't start taking it on their own." Talking to a doctor first is essential to make sure you're not at increased risk of bleeding.

Very Low-Risk Men and Women Who May Not Want Aspirin Therapy

Low-risk people include men under 40 and women under 50. While it helps to know that aspirin does reduce healthy people's risk of heart disease and stroke, their risk is low to begin with. And daily aspirin may increase their risk of internal bleeding. For example, if 1,000 healthy people took an aspirin daily for about six years:

  • Daily aspirin would prevent three or four serious cardiovascular events (heart attacks, strokes, or heart disease deaths).
  • However, aspirin would cause about three life-threatening gastrointestinal bleeds.

Unless you have risk factors for heart disease, an aspirin won't help, and may do harm. Talk to a doctor before taking daily aspirin -- because you probably shouldn't.

Low to Medium Risk: Your Choice on Aspirin Therapy

So people at high risk should take an aspirin, and people at very low risk shouldn't. What about everyone in between -- the vast majority of us?

The answer is: it depends. Jacobson suggests putting this question to your doctor: Am I at high enough cardiovascular risk to justify taking an aspirin, even with the small but real risk of significant bleeding?

"The more risk factors that you have, the greater the chance that you will benefit" from daily aspirin, Jacobson tells WebMD.

Your doctor can calculate your cardiovascular disease risks based on the following factors:

  • Your medical history
  • Age
  • Smoking
  • High blood pressure
  • Total and "good" cholesterol levels
  • History of heart disease in close relatives

If you know your blood pressure and cholesterol, you can calculate your own 10-year risk of serious cardiovascular disease using the same tool that doctors use. Called the "Framingham risk calculator," it's available online at:

If the benefits do outweigh the risks for you, how much aspirin should you take? Talk to your doctor first. The standard dose is one baby aspirin (81 milligrams) a day. Higher doses are no more effective, and can cause more stomach upset.

Aspirin: Different Benefits for Men and Women

When it comes to heart attacks and strokes, men and women are not created equal. Women develop cardiovascular disease later than men -- usually after menopause, and often well into their 70s. Their disease symptoms and survival can be very different from men.

For many women, this difference means the risk of cardiovascular disease doesn't justify aspirin until later in life. However, the risk of bleeding while on aspirin also goes up with age, making the choice more complicated.

And women are different from men when it comes to the response to aspirin as well, says Nanette Wenger, MD, spokesperson for the American Heart Association. Based on study data:

  • For healthy men aspirin seems to prevent heart attacks, but not strokes.
  • For healthy women under 65, aspirin prevents strokes, but not heart attacks.
  • For healthy women over 65, aspirin appears to prevent heart attacks similarly to men.

In general, for healthy women under 65, an aspirin isn't recommended, says Wenger. Again, it's best to talk to your doctor.

Most of all, it's important to recognize that taking aspirin doesn't reduce the risk of cardiovascular disease nearly as much as good old-fashioned measures like losing weight, exercising, quitting smoking, and controlling blood pressure and cholesterol. These measures can lower the risk of serious disease by up to 80% according to some studies -- leaving aspirin in the dust.

Yet aspirin is a valuable tool for people who want to do everything they can to prevent heart attacks and stroke. After seeing her doctor, Sandra Rose decided she was one of them. She decided to stay on her aspirin, even though her cardiovascular risk was already low. "I wanted to get it even lower," she said, despite the risk of bleeding. Knowing the benefits, and the risks, let her make an informed choice.

WebMD Feature


SOURCES: Sandra Rose, MS, nurse, Raleigh, N.C. American Heart Association web site. U.S. Preventive Services Task Force web site. Terry Jacobson, MD, director, Office of Health Promotion and Disease Prevention, Emory University, Atlanta. Nanette Wenger, MD, professor of medicine, Emory University School of Medicine; chair of cardiology, Grady Memorial Hospital; spokeswoman, American Heart Association. Berger, et al, The Journal of the American Medical Association, January 18, 2006. WebMD Medical News: "Aspirin Benefits Differ for Men, Women."

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