Aspirin Gets Demoted for Heart Attack and Stroke Prevention

New guidelines no longer recommend this drug for certain age groups

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Before there was widespread use of statins to lower blood cholesterol, before the medical community found better strategies for treating high blood pressure, and before the public understood the cardiovascular benefits of eating less saturated fat and engaging in more physical activity, aspirin stood out as a way to prevent heart attacks and strokes. A 1989 study on men, for instance, showed that taking an aspirin every other day reduced heart attack risk by 44 percent. That was no small thing, as heart attacks and strokes have long been the leading cause of death in the U.S.

But more recent research analyzed by the U.S. Preventive Services Task Force suggests that daily low-dose aspirin (sometimes called baby aspirin, which contains a quarter of the aspirin in a regular aspirin tablet) reduces the risk of a heart attack or stroke by a relatively modest 12 percent, on average. The Task Force says that the high rate of statin and antihypertensive use diminishes aspirin’s contribution to cardiovascular health. At the same time, the Task Force points to studies that show aspirin use increases the risk for major gastrointestinal bleeding by 58 percent, while the risk for hemorrhagic stroke (bleeding in the brain) more than doubles. Aspirin has an anti-clotting effect, making bleeding more likely.

Because of numbers like that, which make it much more important to weigh benefits against risks, the Task Force recently revised its 2016 recommendations on taking aspirin to reduce the risk of heart attacks and strokes. It now gives this practice a lower grade for several age groups.

Here are the changes. But first, bear in mind that these recommendations are for primary prevention, meaning they are intended for people who have never had a heart attack or stroke. Aspirin recommendations differ for secondary prevention—that is, for trying to avoid another cardiovascular event. People who have already had a heart attack, stroke, or coronary artery bypass surgery, as well as those who have a high coronary calcium score (as measured by a special CT scan) or angina, should have a conversation with their doctor about taking aspirin.

Ages 40 through 49

2016: Six years ago there was no recommendation on aspirin for people in this age group. There was not enough evidence to support one.

2022: Enough evidence has come in that on a scale of A through D, the Task Force has assigned a passing (but not high) grade of C to the practice of taking a daily baby aspirin for those in this age group who have at least a 10 percent chance of having a heart attack or stroke within the next 10 years (see box below). But the advice, which it says will result in a “modest net benefit,” comes with a caveat: No one in their 40s should start taking baby aspirin daily if they have an increased risk for bleeding due to such conditions as diabetes or high blood pressure or because they have a history of any one of a variety of gastrointestinal disorders. Nor should they ingest aspirin daily if they regularly take a nonsteroidal anti-inflammatory drug (NSAID) like ibuprofen or naproxen. NSAIDs are commonly taken by people who have arthritis or other inflammatory or painful conditions, but like aspirin (itself an NSAID), they increase the risk of gastrointestinal bleeding. The cumulative risk of taking two or more drugs that increase the risk of bleeding outweighs the cardiovascular protection afforded by the aspirin.

Even for those who do not have a bleeding issue, it’s not a blanket recommendation to take aspirin. It’s an individual decision, the Task Force says; if you’re in your 40s, you should discuss the idea with your doctor before making low-dose aspirin part of your daily routine.

Ages 50 through 59

2016: Initiating low-dose aspirin as a preventive therapy was assigned the grade of B for anyone in this age group who had at least a 10 percent risk of having a heart attack or stroke within the next 10 years. It was a blanket recommendation, in fact, as long as the person did not have an increased risk for bleeding. Those with such a risk were not advised to begin an aspirin regimen.

2022: The Task Force’s grade for starting a low-dose aspirin regimen in your 50s has been downgraded to a C. And it’s no longer a blanket recommendation but an individual decision to be discussed with your doctor. Even for those without a bleeding risk, the benefit of preventing heart disease must be weighed against the possibility of internal bleeding; advancing age alone increases bleeding risk.

Ages 60 through 69

2016: Initiating a daily low-dose aspirin regimen if you had at least a 10 percent risk of suffering a heart attack or stroke over the next 10 years had a grade of C. It was not automatically supposed to become part of your daily life. Rather, the decision needed to be made in conjunction with your physician.

2022: The Task Force now recommends against starting an aspirin regimen, giving it a grade of D for people in this age group. The bleeding risks are simply too high.

Ages 70 and older

2016: The assumption was that if you started an aspirin regimen in an earlier decade of life, you would continue taking it for the rest of your life.

2022: The Task Force now recommends that if you began taking low-dose aspirin daily when you were younger, you should consider discontinuing the practice in consultation with your doctor because of the increased bleeding risk. “There is generally little incremental lifetime net benefit in continuing aspirin use beyond the age of 75 to 80 years,” the Task Force says.

Determining Your 10-Year Risk

The U.S. Preventive Services Task Force consistently says that anyone considering an aspirin regimen to lower the risk for heart attack and stroke should have at least a 10 percent chance of having one of those events in the next 10 years. So, how do you figure out your risk?

You should discuss the odds with your physician, of course, but you can also use this online Heart Risk Calculator, issued jointly by the American College of Cardiology and the American Heart Association. You plug in information that includes your sex, age, race, total cholesterol, HDL cholesterol, and systolic blood pressure (the top number in a blood pressure reading), and the calculator shoots out a number.

For instance, if you’re a 48-year-old white man with a total blood cholesterol count of 200, HDL of 40, and systolic blood pressure of 130 and do not have diabetes or a smoking habit, your risk for having a cardiovascular event within the next 10 years is 3.7 percent. If you’re that same man with the same numbers at age 50, your risk goes up to 4.5 percent. In both scenarios, you are not a candidate for daily low-dose aspirin. But if you’re 59 with those numbers and now need medicine to keep your systolic blood pressure down to 130, your risk for having a cardiovascular event over the next 10 years rises to 11.2 percent.

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