Are DOACs Safer Than Warfarin for Patients With AFib?

Direct oral anticoagulants (DOACs) appear to be safer than warfarin for patients with atrial fibrillation (AF), according to a new study. 

“DOACs have a favorable bleeding risk profile in patients with AF,” the researchers wrote. “However, the safety of individual DOACs relative to warfarin for specific bleeding outcomes is less certain.”

After comparing the bleeding safety profile of warfarin with those of rivaroxaban, dabigatran, and apixaban, the researchers found that DOACs have a favorable bleeding safety profile compared with warfarin—though the profile associated with individual DOACs are not identical among patients with AF.

To reach this conclusion, the researchers identified 423,450 patients with AF between 2013 to 2015 in the National Cardiovascular Data Registry PINNACLE national ambulatory registry, matched to the Centers for Medicare and Medicaid Services database.

In all, 64% of the patients with AF had received oral anticoagulant therapy. Of these patients, 66% received warfarin, 15% received rivaroxaban, 12% received dabigatran, and 7% received apixaban.

The median duration of follow-up was 1.4 years. Outcomes included time to first major bleed, intracranial hemorrhage (ICH), major gastrointestinal bleed (GIB), or other major bleed; 6.9% of patients had experienced a major bleed.

Patients who had received rivaroxaban, dabigatran, or apixaban were less likely to have experienced ICH than patients who had received warfarin. 

The researchers suggest that, in terms of safety, DOACs are superior to warfarin among patients with AF. However, the exception is with rivaroxaban and GIB—the risk of major GIB was higher among those who had received rivaroxaban and lower among those who had received dabigatran or apixaban. And relative to warfarin, rivaroxaban was also associated with higher GIB risk.

For any DOAC vs warfarin, age interacted with major bleeding, GIB, and other major bleeding. Being aged 75 years or older attenuated the relative safety benefits of DOACs, with those in this age group who had received a DOAC having less safety benefit relative to those who had received warfarin. 

—Colleen Murphy

Reference:

Wong JM, Maddox TM, Kennedy K, Shaw RE. Comparing major bleeding risk in outpatients with atrial fibrillation or flutter by oral anticoagulant type (from the National Cardiovascular Disease Registry's Practice Innovation and Clinical Excellence Registry). Am J Cardiol. 2020;125(10):1500-1507. doi:10.1016/j.amjcard.2020.02.028