The US Food and Drug Administration concludes that daily aspirin use can help ward off a heart attack or stroke in some people, but it is not for everyone.
The federal agency says while there is evidence that low-dose aspirin can prevent heart attacks, strokes and cardiovascular problems reoccurring (so-called secondary prevention), the case has yet to be made for using it to prevent a first event (primary prevention).
Aspirin works by interfering with the blood's clotting action, so reducing the chance of clots developing and obstructing flow of oxygen and blood. Clots that obstruct a coronary artery are a cause of heart attacks, while blockages in the blood supply to the brain are a cause of stroke.
The Food and Drug Administration (FDA) draw these conclusions after "carefully examining scientific data from major studies," according to a new Consumer Update.
Dr. Robert Temple, FDA's deputy director for clinical science, says:
"Since the 1990s, clinical data have shown that in people who have experienced a heart attack, stroke or who have a disease of the blood vessels in the heart, a daily low dose of aspirin can help prevent a reoccurrence."
For primary prevention, 'benefits not established, while risks are still present'
But for people who have not had a heart attack, stroke or cardiovascular problems, "the benefit has not been established but risks - such as dangerous bleeding into the brain or stomach - are still present," warn the FDA.
There is insufficient evidence to support use of low-dose aspirin to prevent heart attack and stroke in people who have not had one before, say the FDA.
And neither does the data support the use of aspirin to prevent heart attack or stroke in people who have never had them but have a family history of them or are showing evidence of arterial disease, it adds.
However, large trials looking at use of aspirin in primary prevention of heart attack and stroke are ongoing, and the FDA will continue to monitor them and update consumers should the evidence change.
"The bottom line is," say the FDA, "that in people who have had a heart attack, stroke or cardiovascular problems, daily aspirin therapy is worth considering."
If you are considering using daily aspirin, says Dr. Temple, you should only do so after talking to your doctor, who can help you weigh the benefits and the risks.
How much aspirin you take is important, he adds. Your doctor should ensure the dose you take and how often you take it is right for you, and recommend the dose and frequency that will bring you the greatest benefit with the fewest side effects.
Aspirin doses range from low-strength, as in an 80 mg tablet, to regular strength, as in a 325 mg tablet.
Also, because aspirin reduces risk of blood clotting, care is needed when using it with other blood thinners like warfarin, dabigatran (Pradaxa), rivaroxaban (Xarelto) and apixaban (Eliquis), warn the FDA.
And, if your doctor recommends daily aspirin to lower your risk of heart attack and clot-related stroke, you should read the labels carefully to make sure you use the correct product. Some combine aspirin with other painkillers and ingredients and should not be taken for long-term use.
Medical News Today recently reported on research that found use of low-dose aspirin is linked to improved colon cancer survival, while an earlier study showed regular aspirin is linked to age-related macular degeneration risk.