For dialysis patients with atrial fibrillation (AFib), the direct oral anticoagulant (DOAC) apixaban is associated with lower risk for major bleeding compared with warfarin, a new study finds.
Using the United States Renal Data System database (October 2010 to December 2015), Konstantinos Siontis, MD, of the University of Michigan Cardiovascular Center in Ann Arbor, and colleagues matched 2351 Medicare recipients (mean age 68 years) treated with apixaban to 23,172 treated with warfarin. During the study period, apixaban was increasingly adopted, and it represented a quarter of new anticoagulant prescriptions in 2015.
Comparative analyses published in Circulation showed no significant differences between anticoagulants in the risks for stroke or systemic embolism. Apixaban, however, was associated with a significant 28% lower risk for major bleeding than warfarin.
Dosage was an important factor. Standard-dose apixaban (5 mg twice a day), but not reduced-dose apixaban (2.5 mg twice a day dose), was associated with lower risks for thromboembolism and mortality compared with warfarin. The investigators observed no differences in risk for major bleeding between the 2 doses.
“Apixaban appears to be safer across the spectrum of kidney function categories, possibly owing to its predominantly non-renal elimination,” Dr Siontis and his team explained. “The results of the current analysis are in contradistinction to the bleeding-related morbidity and mortality attributed to dabigatran and rivaroxaban in a previous analysis of hemodialysis patients, suggesting that the increased bleeding risk in ESKD [end-stage kidney disease] is not a drug class effect for all DOACs.”
Two-thirds of patients taking apixaban or warfarin discontinued anticoagulant therapy within a year.
Siontis KC, Zhang X, Eckard A, et al. Outcomes associated with apixaban use in end-stage kidney disease patients with atrial fibrillation in the United States. Circ. DOI: 10.1161/CIRCULATIONAHA.118.03541