Evaluation of Patient Characteristics Linked to Major Bleeding Events in Patients Prescribed Direct Oral Anticoagulants

INTRODUCTION: Direct oral anticoagulants (DOACs) demonstrated similar efficacy and lower risk of intracranial hemorrhage than warfarin in patients with atrial fibrillation and venous thromboembolism. Given the lack of data identifying risk factors in patients who bled while on a DOAC, we sought to investigate these characteristics. MATERIALS AND METHODS: This retrospective chart review was approved by the Mass General Brigham Institutional Review Board and assessed patients who experienced bleeding events while on DOAC therapy from 6/1/2015 to 7/1/2020. Patient characteristics were evaluated, including age, sex, body mass index (BMI), renal function, concomitant therapies, and baseline comorbidities. RESULTS: Eighty-seven patients were included for analysis, with a median age of 75.8 years. Most patients were female (51.7%) and 24 (27.6%) had a BMI >30. At time-of-event, 21 patients (24.1%) had acute kidney injury. Thirty-three patients (37.9%) were on concomitant antiplatelet therapy (APT), with 31 (35.6%) on single APT and 2 on dual APT. Pertinent comorbidities included hypertension (74.7%), ischemic cerebrovascular accident (28.7%), thyroid abnormality (23.0%), active cancer (14.9%), and anemia (13.8%). Eleven patients (12.6%) had a prior bleeding event. Most patients were on apixaban (69.0%) for the indication of stroke prevention in nonvalvular atrial fibrillation/flutter (72.4%). FDA-approved dosing was used in most patients (92.0%), and all deviations reflected underdosing. Most bleeding events were defined as major (95.4%), occurred at a critical organ site (72.4%), and developed spontaneously (58.6%). CONCLUSIONS: These data provide insight into characteristics of patients who experience bleeding events while on DOAC therapy. Understanding these potential risk factors may optimize the safe use of these agents.