S1443 Impact of Direct Oral Anticoagulants (DOACs) vs Warfarin on Outcomes in Acute GI Bleeding

Introduction: Direct-acting oral anticoagulants and Warfarin are being increasingly utilized for anticoagulation but, studies are mixed regarding the comparative risk for gastrointestinal bleeding (GIB) associated with these therapies. Some studies suggest that GIBs are lower in patients on DOACs but, there are contradictory studies as well. The objective of this study was to evaluate the risk of GIB in patients with atrial fibrillation on DOACs compared to Warfarin and also overall mortality. Methods: This study was developed using a large de-identified health research network with data from 98 health care organizations (HCO), within the United States (TriNetX). This study consisted of 2 cohorts. The first cohort being on Warfarin and second cohort being on DOACs (dabigatran, rivaroxaban, apixaban, and edoxaban). Patients were excluded if they had been on the opposite therapy prior, had any other indication for anticoagulation other than atrial fibrillation and were excluded if they were on DVT prophylaxis while hospitalized such as low molecular weight heparin (LMWH) or unfractionated heparin. This study then consisted of 5 queries comparing the cohort’s rates of overall GI bleed, bleeding due to anticoagulation, upper GI bleed (UGIB), lower GI bleed (LGIB), and overall mortality. Within each cohort, we collected data on demographics and several risk factors for GIB, including genetic disorders, renal disease, and acquired bleeding disorders. Then performed propensity score matching (PSM) to control for confounding. Results: This study identified 853 patients in the Warfarin group and 3,855 patients in the DOAC group before matching. After matching, there were 826 patients in both cohorts. Our study found that the risk of GI bleeding was higher in the Warfarin group (n = 254) vs DOAC group (n = 176) (OR 1.64, CI 1.31-2.05, P = 0.00). There was no difference in rates of Upper GI Bleed (OR 0.82, CI 0.41-1.64, P = 0.57) and Lower GI Bleed (OR 1.08, CI 0.71-1.65, P = 0.71) between the 2 cohorts. Overall, mortality was also increased in the Warfarin group (n = 183) vs DOAC group (n = 73) (OR 2.94, CI 2.19-3.93, P = 0.00). Conclusion: This retrospective study concluded that patients on Warfarin have a statistically significant increased risk of GI bleeding and mortality as compared to those on DOACs. Future prospective studies are needed to further assess the clinical safety of both therapies in high-risk groups for GI bleeds.