NOACs Versus Warfarin in NVAF with Prior Bleeding

In patients with non-valvular atrial fibrillation (NVAF), the use of non-vitamin K antagonist oral anticoagulants (NOACs) was associated with a comparable or reduced risk of stroke or systemic embolism (SE) and major bleeding (MB) compared with warfarin use, according to an article in the Journal of Thrombosis and Thrombolysis. The authors also noted a “variable risk” for stroke, SE, or MB between different NOACs.

Primary investigator Gregory Y. H. Lip and colleagues based these findings on a retrospective analysis of real-world patients with NVAF, identified from a claims database, who had experienced prior bleeding events and were receiving warfarin or a NOAC. Patients were stratified by individual NOAC or warfarin use. The researchers used Cox models to estimate risk of stroke, SE, and MB.

In the cohort of 244,563 patients with AF and prior bleeding, 55,094 (22.5%) received apixaban, 12,500 (5.1%) received dabigatran, 38,246 (15.6%) received rivaroxaban, and 138,723 (56.7%) received warfarin. According to the authors, apixaban (hazard ratio [HR] = 0.76; 95% confidence interval [CI], 0.70–0.83) and rivaroxaban (HR = 0.79; 95% CI, 0.71–0.87) exhibited lower risk of stroke and SE compared with warfarin. Comparatively, apixaban (HR = 0.67; 95% CI, 0.64–0.70) and dabigatran (HR = 0.88; 95% CI, 0.81–0.96) had a lower risk of MB compared with warfarin.

When comparing NOACs against each other, Lip and the researchers observed that “apixaban patients had a lower risk of stroke/SE vs. dabigatran (HR = 0.70; 95% CI, 0.57–0.86) and rivaroxaban (HR = 0.85; 95% CI, 0.76–0.96) and a lower risk of MB than dabigatran (HR = 0.73; 95% CI, 0.67–0.81) and rivaroxaban (HR = 0.64; 95% CI, 0.61–0.68).”

This was, to the authors’ knowledge, the first “real-world” study to compare outcomes of stroke, SE, and MB between individual NOACs and warfarin, and they ultimately concluded that “treatment with NOACs was associated with similar or lower risk of stroke/SE and MB compared with warfarin and variable risk of stroke/SE and MB against each other.”