Comparison of Apixaban With Warfarin in Patients on Dialysis Within an Integrated Health Care System

The risk and benefit for patients on dialysis receiving anticoagulation (AC) therapy have not been clearly established. This study aimed to compare the rates of clinically significant thrombotic and bleeding events in patients on dialysis.

This is a retrospective cohort study conducted using Kaiser Permanente Northern California's electronic medical record database from 2013 to 2021. Patients over 18 years old on dialysis who were prescribed warfarin or apixaban were included. Patients with mechanical valves were excluded. The outcomes were analyzed using Mann-Whitney tests for continuous variables, χ² tests for categorical variables, and Kaplan-Meier method for time-to-event analysis.

In the study period, 9832 patients were not on AC, and 2088 were taking apixaban or warfarin. The baseline demographics (age, Charlson Comorbidity Index, and sex) were comparable between apixaban and warfarin groups. Among the patients on anticoagulants, 181 were taking apixaban, while 1907 were taking only warfarin. The outcomes 1-3 years within the study period showed that the rates of clinically significant bleeding and thrombosis were comparable in both groups, with the exception of the rate of dialysis access thrombosis being lower in the apixaban group (7% vs 17%, P < .001).

In this diverse cohort, apixaban and warfarin showed no clinically significant differences in bleeding rates and lower rate of access thrombosis with apixaban. This study adds to the growing data of AC in the population with end-stage kidney disease, highlighting the need to enroll patients in an adequately powered randomized controlled trial to inform future practice.