An unusual research in which thousands of heart attack patients enrolled themselves and tracked their wellbeing electronically as they took low- or regular-strength aspirin concluded that all concentrations seem to be similarly healthy and reliable for avoiding further heart attacks and strokes.
However, there is a significant disclaimer: people have such a particular fondness for the lower dose that it is uncertain if the data will determine that the drugs are completely equal, according to some independent analysts. Half of those who were advised to take the higher dose either took the lower dose or stopped taking aspirin entirely.
“Patients basically decided for themselves” what they wanted to take because they bought the aspirin on their own, said Dr. Salim Virani, a cardiologist at Baylor College of Medicine in Houston who had no role in the study.
Nonetheless, the findings suggest that there is no need to take the higher dosage, 325 milligrams, which many physicians thought would be more effective than 81-milligram “baby aspirin,” he added.
The findings were announced in the New England Journal of Medicine on Saturday and presented at an American College of Cardiology meeting.
While aspirin can help avoid blood clots, it isn’t recommended for healthy people who haven’t yet experienced heart disease because it can trigger bleeding. However, for those who have previously had a heart attack, bypass surgery, or clogged arteries involving a stent, the effects are apparent.
The best dosage, however, is unknown, and the study’s aim was to compare them in a real-world environment. The Patient-Centered Outcomes Research Institute was established under the 2010 Patient Protection and Affordable Care Act to assist patients in making better health choices.
Almost 15,000 people were invited to join via mail, email, or phone call, and they registered on a website, returning every three to six months for follow-up. Respondents’ patient history was gathered from their electronic reports and insurance claims by a network of participating health centers.
The patients were selected at random to take either reduced- or regular-dose aspirin, which they purchased over the counter. Virani explained that since almost everyone was taking aspirin even before research started, and 85 percent were still on a low dosage, “it was an uphill challenge right from the start” to get people to take the dose they were given.
Within two years, about 7% of each party had died or been treated for a heart attack or stroke. The safety outcomes were also comparable, with less than 1% experiencing serious bleeding necessitating hospitalization and a transfusion.
Nearly 41% of those assigned to take the higher dose switched at some point to the lower one, and that high rate “could have obscured a true difference” in safety or effectiveness, Colin Baigent, a medical scientist at the University of Oxford in the United Kingdom, wrote in a commentary in the medical journal.
According to Dr. Schuyler Jones of Duke University, one of the study’s leaders, the study also offers useful advice. If patients are now taking low-dose aspirin, “staying on the dose rather than moving is the correct choice,” he says. Individuals who are doing well on 325 milligrams may want to stick with that and may see their physicians if they have any questions.
“In general, we’re going to consider continuing with the low dose,” Jones said of new patients.
According to Virani, patients must note that aspirin is a drug and that, even though it is available over the counter, patients should not make decisions about its use on their own.