Analysis of the Risk Factors Associated with Minor Bleeding in Patients with Venous Thromboembolism during Treatment with Direct Oral Anticoagulants

: Direct oral anticoagulants (DOACs) are safe and efficacious when compared to warfarin for patients with venous thromboembolism (VTE). However, bleeding is a major side effect of anticoagulant therapy in VTE patients. Discontinuation of the DOACs associated to adverse events such as bleeding. The HAS-BLED score predicts warfarin-associated hemorrhage. However, little is known about risk factors for DOAC-associated minor bleeding in VTE patients. We aimed to identify risk factors for minor bleeding in VTE patients that were treated with edoxaban, rivaroxaban, or apixaban. We retrospectively evaluated the data of 212 VTE patients who received treatment with a DOAC. The study endpoint was defined as the occurrence of minor bleeding. Logistic regression analysis was used to determine risk factors that were significantly associated with minor bleeding. A total of 36 (17.0%) patients experienced minor bleeding, with rates of 15.7%, 0%, and 21.3% for edoxaban, rivaroxaban, and apixaban, respectively. In the multivariate analysis, bleeding history or predisposition [odds ratio (OR) 6.083, 95% confidence interval (CI) 2.131-17.364, p=0.001] and cancer (OR 6.397, 95% CI 2.858-14.317, p<0.001) were significantly associated with minor bleeding. Bleeding history or predisposition and cancer were the most important risk factors for DOAC-induced minor bleeding in VTE patients in this study. To continue anticoagulant therapy of the DOACs, further management systems by minor bleeding risk factors for patients with VTE will be required.