Heart disease researchers have identified a group of patients for whom international guidelines on the use of aspirin for heart health may not apply.

In a study published in a journal Circulationa review of data from three clinical trials, calls into question current best practices for using the drug for the primary prevention of heart disease and stroke, known as atherosclerotic cardiovascular disease. .

The study examined the results of a clinical trial published in 2018 that included more than 47,000 patients in 10 countries, including the United States, United Kingdom, and Australia.

The analysis focused on the results of a subgroup of 7,222 patients who were already taking aspirin before the three trials began. The people in the study were at high risk for cardiovascular disease and were taking aspirin to prevent a first heart attack or stroke.

The data showed that patients who took aspirin before the trial and then stopped had a higher risk of heart disease and stroke (12.5% ​​vs. 10.4%) than those who continued taking it.

The analysis also found no significant statistical difference in the risk of major bleeding between the two patient groups.

The research team said this data shows that further evidence is needed about best practices in adults who already take aspirin to prevent cardiovascular disease.

The study was conducted by Professor J. William McEvoy, an established professor of preventive cardiology at the University of Galway and consultant cardiologist at Saolta University Healthcare Group, in collaboration with researchers from the University of Tasmania and Monash University in Melbourne. I took the lead.

Professor McEvoy said: “We challenged the notion that aspirin withdrawal is a one-size-fits-all approach.”

The research team found that adults who were first prescribed aspirin to reduce their risk of heart attack or stroke, but then chose to stop taking it without being told, had a 28% lower risk of heart disease and stroke. We focused on the results of observational studies that suggest a higher percentage. Doctors do that.

Based largely on three major clinical trials published in 2018, international guidelines no longer recommend the routine use of aspirin to prevent first heart attacks and strokes.

Importantly, aspirin is still recommended for high-risk adults who have already had heart disease or stroke to reduce the risk of secondary events.

The shift away from primary prevention aspirin in recent guidelines was motivated by the increased risk of major bleeding seen with this common drug in three trials, but major bleeding is relatively rare with aspirin and It was most evident only among trial participants who started, but not among those who had previously taken aspirin safely, during the trial.

These trials primarily tested the effects of starting aspirin in adults who had not previously been treated with aspirin to reduce the risk of atherosclerotic cardiovascular disease. Less is known about what to do in the common scenario of adults who are already safely taking aspirin for primary prevention.

Professor McEvoy said: “Our findings about the benefits of aspirin in reducing heart disease and stroke without excessive bleeding risk in some patients who already take aspirin without having bleeding problems. “This may be due to the fact that adults are inherently at lower future risk.” So they seem to be getting more of the benefits of aspirin with less risk.

“While these results are hypothesis-generating, they are the best data available at this time. Until further evidence is available, people already safely treated with low-dose aspirin for primary prevention should not It seems safe to continue unless you have risk factors for aspirin-related bleeding. ”