A person holds two aspirin tablets in one hand, and a glass of water in the other.
People can take aspirin to prevent cardiovascular disease, but there is an additional benefit for colorectal cancer protection. (For Spectrum Health Beat)

Daily low-dose aspirin is best used as a preventive measure against heart disease for people in their 50s, top U.S. experts in preventive medicine have determined.

People in their 60s also can take low-dose aspirin to reduce their risk of heart attack and stroke, but they will not benefit as much, the U.S. Preventive Services Task Force stated in a set of draft recommendations issued Monday.

The new guidelines serve as a refinement of the task force’s last set of aspirin recommendations. Published in 2009, they suggested that low-dose aspirin could help men 45 to 79 and women 55 to 79 prevent heart disease.

“In this recommendation, we try to provide additional guidance about who is most likely to achieve benefits from aspirin,” said Dr. Doug Owens, a member of the task force and a professor of medicine at Stanford University.

Based on new evidence, the task force concluded there’s insufficient evidence to recommend low-dose aspirin to prevent heart disease in people younger than 50, or 70 and older.

The draft recommendations also noted for the first time that aspirin taken to prevent heart disease also appears to decrease risk of colon cancer.

However, the task force is not recommending that aspirin be used solely to prevent colon cancer, Owens added.

“We think for people taking aspirin to prevent cardiovascular disease, there is an additional benefit for colorectal cancer protection,” Owens said. “We’re not recommending you take aspirin for colorectal cancer if you’re not at high risk for cardiovascular disease.”

The task force recommendations only apply to people at increased risk for heart disease, not people who have had a heart attack or stroke and are trying to prevent a second episode, said Dr. Elliott Antman, immediate past president of the American Heart Association. Antman is a professor and associate dean for clinical/translational research at Harvard Medical School in Boston.

The American Heart Association and the American College of Cardiology in 2013 unveiled a new risk calculator for heart disease, which the task force used in making its recommendations, Antman said.

People in their 50s who have a 10 percent or greater risk of developing heart disease over the next 10 years and are not at increased risk for bleeding have the best chance of benefitting from 81 milligrams (mg) of aspirin taken every day, the task force concluded.

“If your cardiovascular risk calculation turns out to be 10 percent or greater, that’s a signal you should have a conversation with your physician about the risks and benefits of low-dose aspirin and whether it’s right for you,” Antman said.

People in their 60s might also benefit if they have a 10 percent or greater risk of heart disease during the next decade, but the task force said that’s an “individual” decision, and the net benefit “is at least small.”

People in that age range “who place a higher value on the potential benefits than the potential harms may choose to use low-dose aspirin,” the task force said in a summary of its recommendations.

Owens said that no matter your age, you should talk with your doctor before starting to take aspirin. Even at low doses, aspirin can cause gastrointestinal bleeding and other potential health problems.

“We believe that everyone should make this decision after a discussion with a clinician, because there are many factors to consider,” he said.

Antman added that people should not consider aspirin a “get out of jail free” card for heart disease, which will allow them to smoke, eat unhealthy food and avoid exercise.

“All of this is recommended in the context of living a healthy lifestyle,” he said.

And Dr. Kim Williams, president of the American College of Cardiology, reiterated that these guidelines only refer to taking a low (81 mg) dose of aspirin once daily.

“Aspirin definitely causes GI bleeding, related to the dose rather than the duration,” Williams said. “If you’ve taken low-dose aspirin safely for five years, your bleeding risk is the same as if you’ve just started taking it.”

The task force is an independent, volunteer panel of national experts in prevention and evidence-based medicine.