Risk of Bleeding Among Individuals on Direct-Acting Oral Anticoagulants: An Academic Medical Center Cohort Study

Abstract

Previous research has identified risk factors that may affect the risk of bleeding when individuals are exposed to oral anticoagulants. It is unclear if the risk continues to exist with the direct oral anticoagulants (DOACs). The purpose of this study was to assess the risk of bleeding in patients on DOACs (apixaban, rivaroxaban, dabigatran, edoxaban, and betrixaban) based on known risk factors including demographics, medical conditions, and concomitant medications. This study was a retrospective analysis using electronic health record data from the University of Utah Hospital (Division of Cardiovascular Medicine) of individuals receiving a DOAC from 2015 to 2020. The primary outcome of interest was bleeding events [gastrointestinal (GI) bleeding, other anatomical site bleeding (excluding GI), and any bleeding] recorded in the electronic health record that codes using International Classification of Diseases 9th and 10th codes. Known risk factors were used to predict bleeding using multivariate logistic regression. A total of 5492 patients received a DOAC during the study period. Less than half the study population were female (2287, 41.6%). During the follow-up, there were 988 patients (18.0%) experiencing a bleeding event. Of them, 351 patients (35.5%) had a GI bleeding event. Significant risk factors of GI bleeding included clopidogrel [odds ratio (OR) 1.71; 95% confidence interval (95% CI), 1.16-2.52] and previous GI bleeding episodes (OR 7.73; 95% CI, 5.36-11.16). Exposure to corticosteroids (OR 1.50; 95% CI, 1.20-1.87) and previous GI bleeding (OR 1.61; 95% CI, 1.10-2.35) were associated with an increase in bleeding at other anatomical sites (not GI included).