More than 10% of patients in the United States receiving daily low-dose aspirin to prevent a heart attack or stroke have likely been prescribed the medicine inappropriately and may be doing more harm than good.
Researchers at Baylor College of Medicine and other health institutions studied records of about 69,000 people taking aspirin daily for the primary purpose of preventing heart attack and stroke. The team determined that over 1 in 10 did not need to take the medication because their risk of heart disease was too low to warrant daily aspirin treatment, according to ABC News.
The researchers said that because aspirin is an over-the-counter medication, misuse may be higher than their study indicates as many people may be medicating themselves. Last year, the Food and Drug Administration warned against the general use of aspirin for primary prevention against heart disease and stroke, and denied a request to market the medication for this use, according to Medical News Today.
[quote text_size=”small” author=”– Freek W.A. Verheugt” author_title=”Professor of cardiology at the Heart and Lung Center”]
Major coronary events are reduced 18% by aspirin, but at the cost of an increase of 54% of major extracranial bleeding. Each two major coronary events have shown to be prevented by prophylactic aspirin at the cost of one major extracranial bleed.
To determine what constitutes inappropriate prescribing of aspirin, the researchers evaluated guidelines from the American Heart Association and the US Preventative Services Task Force, among others. Researchers determined that daily aspirin use would be inappropriate in patients with a 10-year cardiovascular risk lower than 6%.
This rule was then used to analyze data on more than 69,000 patients receiving aspirin therapy to prevent cardiovascular disease. Researchers excluded patients who had already experienced a cardiovascular event or heart conditions.
Along with finding that 12% of patients in the nationwide sample most likely should not have been prescribed daily aspirin, the team also found that the patients prescribed the medication inappropriately were 16 years younger than those who were given the treatment appropriately, on average.
In some cardiology practices, the researchers found that up to 72% of patients were taking aspirin even though they did not have a high enough risk factor, while other practices had 0%.
Aspirin can help prevent heart attacks and strokes by preventing the formation of blood clots, which are made up of platelets that stick together with the help of an enzyme called COX. Aspirin prevents COX from helping blood clots form.
The authors noted that there is no evidence that aspirin reduces the risk of a first heart attack or stroke in people who have a low risk of cardiovascular disease or no history of heart problems. Daily aspirin use has been linked to an increased risk of bleeding in the stomach or gut and hemorrhagic strokes, as blood that cannot clot easily runs the risk of excessive bleeding, according to the Los Angeles Times.