Many Prescribed Aspirin With Blood Thinners, Despite Bleeding Risk And No Clear Benefits: Study

The findings of new research suggest that taking blood thinners like Xarelto or Eliquis together with aspirin may increase the risk of both serious bleeding problems and hospitalization, while providing no meaningful benefits for users.

In a study published this week in the medical journal JAMA Internal Medicine, researchers from the University of Michigan raise serious questions about the common practice of combining direct oral anticoagulants and aspirin.

Researchers conducted a registry-based cohort study at four anticoagulation clinics in Michigan from January 2015 to December 2019, involving a total of 3,200 patients undergoing treatment with a direct oral anticoagulant (DOAC) drug for atrial fibrillation or venous thromboembolism. Those drugs include Xarelto, Pradaxa, and Eliquis and were used to help prevent blood clots and strokes. Patients did not have a history of heart valve replacement or recent acute coronary syndrome.

Participants were separated into two groups, including one treated with DOACs only and a second group treated with combination therapy of DOAC plus aspirin.

According to the findings, patients treated with combination therapy of a DOAC like Xarelto plus aspirin had significantly higher rates of bleeding, and hospitalizations for bleeding, compared to those only taking DOACs. They also experienced an increased risk of side effects overall.

Combination therapy led to 31 bleeding events per 100 patient years compared to 26 in the single therapy group. However, rates of thrombotic events were the same in both groups, meaning the aspirin did not appear to provide clear benefits to account for the increased bleeding risks and hospitalizations.

There were 9.1 hospital admissions per 100 patient years among those who took aspiring and drugs like Xarelto, while those who took DOACs alone only had 6.5 hospital admissions per 100 patient years.

Prior studies have also linked the combination therapy to adverse side effects. One study published in 2019 indicated an increased risk of bleeding with few benefits for the patients.

Another study published last year also highlighted the risk DOACs and aspirin pose to patients and the increased risk of bleeding. The research indicated aspirin alone was just as effective as preventing blood clots as combination therapy.

It is unclear how many patients are treated with direct oral anticoagulants like Eliquis or Xarelto while also being told to take aspirin or using aspirin on their own to try to prevent blood clots and other cardiac events. Yet, the findings of the new research emphasize a need for doctors to change what they recommend to patients and help provide patient education about the risks combination therapy may pose.