More blood thinners are not automatically better, a new study confirms.
The report in JAMA Internal Medicine focuses on the minimal benefits and disadvantages of combining a daily aspirin with a drug from the newer class of anticoagulants that includes apixaban, dabigatran, edoxaban and rivaroxaban.
“The patients with combination therapy had more bleeding, but they did not have less blood clots.”
Patients have taken one of these direct oral anticoagulants, known as DOACs, to prevent strokes of non-valvular atrial fibrillation or for the treatment of venous thromboembolic disease (deep vein thrombosis or pulmonary embolism). The patients in the study did not have another reason to take aspirin, such as a recent history of a heart attack or a history of a heart valve replacement.
The researchers found that nearly one-third of people who prescribed a DOAC also took aspirin without a clear reason to take the aspirin.
“The patients with combination therapy were more likely to bleed, but they had no less blood clots,” says lead author Jordan Schaefer, an assistant professor of internal medicine and a hematologist at Michigan Medicine at the University of Michigan. . “Therefore, it is important that patients ask their doctors if they should use aspirin as a direct oral anticoagulant.”
The combination of an anticoagulant and a platelet platelet may be appropriate for people who have recently had a heart attack, recent coronary stent placement, or bypass surgery; previous mechanical valve operations; or known peripheral artery disease, among other conditions, says co-author Geoffrey Barnes, an assistant professor of internal medicine and a vascular cardiologist at the Michigan Medicine Frankel Cardiovascular Center.
For the others: “combination therapy may not be intentional; rather, the addition of aspirin can be overlooked because it is not in the area of any specialist or general supplier, ”says Barnes.
The authors note that there are many medical conditions and situations where the addition of aspirin with a direct oral anticoagulant has not been adequately studied. Schaefer adds that he and colleagues plan to confirm their findings in a larger, longer-term study because there were not many blood clots during the period of this study, limiting their ability to determine whether aspirin may be beneficial.
Previously, Schaefer and Barnes also reported a significant increase in adverse outcomes for people using both aspirin and warfarin, another type of anticoagulant.
Schaefer originally presented these registry-based cohort study results at the 2019 annual meeting of the American Society of Hematology.
Source: University of Michigan