MIAMI, FLORIDA - APRIL 12:  In this photo illustration, St. Joseph 81 mg asprin tablets are seen on April 12, 2016 in Miami, Florida. The U.S. Preventive Services Task Force has recommended that taking a low-dose asprin daily can help prevent both heart disease and colorectal cancer in adults ages 50 to 69.  (Photo Illustration by Joe Raedle/Getty Images)
Studies: Low-dose aspirin risks may outweigh benefits
02:33 - Source: CNN
CNN  — 

Still taking a daily aspirin to ward off heart attacks? You might want to think again, according to a new review.

Aspirin is still one of the most commonly used medications in the world, even though it’s no longer recommended as a preventative by many health authorities.

There is no evidence that low-dose aspirin — less than 325 milligrams a day — should be taken by most adults in good cardiovascular health, according to a new review of existing research that published Wednesday in the British Journal of Clinical Pharmacology.

The review, which focused on the risks and benefits of low-dose daily aspirin, found that the risk of a major bleeding event as a result of the drug’s blood-thinning effects outweighs the benefit.

US guidance on a daily dose of aspirin changed last year, with the American College of Cardiology and the American Heart Association recommending daily aspirin only for patients who have had a heart attack, stroke or open heart surgery. Advice in the United Kingdom is similar.

This latest analysis, which looked at 67 studies, found that use of low-dose aspirin in people without cardiovascular disease was associated with a 17% lower incidence of cardiovascular events such as heart attack or stroke.

However, it was also associated with a 47% higher risk of gastrointestinal bleeding and a 34% higher risk of bleeding in the skull.

“Our paper confirms that there is no evidence for taking aspirin in primary prevention, i.e. in healthy people,” study authors Dr. Lee Smith, a reader in Physical Activity and Public Health at Anglia Ruskin University in the UK and Dr. Nicola Veronese, a geriatrician at University of Palermo in Italy, said in an email.

“The take home message of our paper is that low dose aspirin is (only) good when you already have a cardiovascular condition.”

However, it’s important to speak to your own doctor before making any changes to the medication you take, experts said.

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The authors also looked at research that supported the use of aspirin in preventing cancer but said that their review discouraged the use of low-dose aspirin in this scenario.

“Low dose aspirin is one of the most commonly used medications in the world. Moreover, our umbrella review suggests that the weight of the risks, particularly bleedings, shouldn’t be considered secondary,” Smith and Veronese said.

Millions of Americans who’ve never had cardiovascular disease could still be taking a daily aspirin to prevent heart disease without a physician’s recommendation, despite the updated guidance that said it may be unnecessary and possibly risky, the study noted.

Given the range of different interventions now available to prevent cardiovascular disease such as statins, blood pressure medication and help quitting smoking and losing weight, the findings of the research called in question the use of aspirin as a preventative.