Summaries of Must-Read Clinical Literature, Guidelines, and FDA Actions
Dabigatran vs Rivaroxaban for Stroke Prevention
JAMA Intern Med; ePub 2016 Oct 3; Graham, et al
In elderly patients with nonvalvular atrial fibrillation (AF), treatment with rivaroxaban 20 mg once daily was associated with statistically significant increases in intracranial hemorrhage (ICH) and major extracranial bleeding, including major gastrointestinal bleeding, compared with dabigatran 150 mg twice daily. This according to a cohort study of 118,891 patients with nonvalvular AF aged ≥65 years, who initiated treatment with dabigatran or rivaroxaban from November 4, 2011, through June 30, 2014. Primary outcome events included thromboembolic stroke, ICH, major extracranial bleeding including major gastrointestinal bleeding, and mortality. Researchers found:
- 2,537 primary outcome events occurred in a total of 52,240 dabigatran-treated and 66,651 rivaroxaban-treated patients contributing 15,524 and 20,199 person-years of on-treatment follow-up.
- Rivaroxaban use was associated with a statistically nonsignificant reduction in thromboembolic stroke (HR, 0.81), statistically significant increases in ICH (HR, 1.65), and major extracranial bleeding (HR, 1.48), and with statistically nonsignificant increase in mortality (HR, 1.15).
- Rivaroxaban use was associated with significantly increased mortality compared with dabigatran use in patients aged ≥75 years or with CHADS2 score >2.
Graham DJ, Reichman ME, Wernecke M. Stroke, bleeding, and mortality risks in elderly Medicare beneficiaries treated with dabigatran or rivaroxaban for nonvalvular atrial fibrillation. [Published online ahead of print October 3, 2016]. JAMA Intern Med. doi:10.1001/jamainternmed.2016.5954.
Many clinicians think of dabigatran and rivaroxaban, the first 2 agents in the class of anticoagulants now referred to as NOACs (non–vitamin K antagonist oral anticoagulants), as having similar outcomes when used to treat atrial fibrillation. This “real-world study” examines outcomes in an unselected population to answer the question of whether there are important differences between the 2 agents. This trial suggests that compared to dabigatran, rivaroxaban has increased intracranial and major extracranial bleeding, and in adults aged >75 years with a CHADS2 score >2, may even lead to increased mortality. While one needs to acknowledge the limitations of observational trials, this is important information. In addition, this trial is a good example of how medications which may never be evaluated in head-to-head randomized blinded trials may be compared using large datasets which can be utilized to answer clinical questions. —Neil Skolnik, MD