The Safety of Direct Oral Anticoagulants Compared to Warfarin in Patients Hospitalized With Acute Kidney Injury

Background: Direct oral anticoagulants (DOACs) are preferred over warfarin for many indications, though their safety has not been well established in patients with acute renal impairment. Objective: The purpose of this study was to evaluate the frequency of bleeding complications associated with DOACs compared with warfarin in patients admitted to the hospital with acute kidney injury (AKI). Methods: This was a retrospective cohort study evaluating patients admitted to the Penn Medicine Lancaster General Hospital with a diagnosis of AKI from October 2017 through September 2021 and receiving therapy with oral anticoagulants. Comparing DOACs with warfarin, the primary endpoint was the percent frequency of composite major and minor bleeding during the admission and within 30 days of discharge. Results: There were 112 hospitalization encounters included in the study. Of these, 42 (37.5%) patients were receiving warfarin and 70 (62.5%) patients were receiving DOAC therapy before admission. There was a higher frequency of the primary endpoint of bleeding in patients receiving DOACs as compared with warfarin, though this was not statistically significant (18.5% vs. 11.9%, respectively, P = 0.432). There were no differences between groups in the frequency of major bleeding, minor bleeding, or transfusions. Patients receiving DOAC therapy were more likely to experience anticoagulation-related readmissions or emergency department visits compared with patients on warfarin therapy (11.4% vs. 0%, P = 0.024). Conclusion and Relevance: Direct oral anticoagulants and warfarin were associated with statistically similar rates of bleeding in patients presenting with AKI. Further research is necessary to elucidate if DOACs are safer than warfarin in this patient population.