Safety and effectiveness of direct oral anticoagulants in fragile patients with venous thromboembolism: a retrospective cohort observational study.

Purpose: The use of direct oral anticoagulants (DOACs) is challenging in fragile patients, including those with cancer, chronic kidney disease (CKD), and old age. We aimed to compare the safety of DOACs in terms of bleeding complications in these patients. Methods: Using hospital data from 2013 to 2019, we compared the risk of bleeding and major bleeding, including intracranial bleeding, any bleeding requiring transfusion, and all-cause bleeding, in patients with venous thromboembolism (VTE) who were naïve to DOAC (n = 12,369) and warfarin (n = 4,123). Hazard ratios (HRs) for the clinical outcomes were analyzed using Cox regression analysis, with warfarin as a reference. Results: The study included 4,078 eligible patients, predominantly female (54.1%), with a mean age of 62.5 years. DOACs were the primary treatment in 74.1% of the patients. DOAC treatment was associated with lower all-cause mortality compared to warfarin (HR, 0.799; 95% confidence interval [CI], 0.707-0.904). Although rates of recurrent VTE or major bleeding did not significantly differ between the groups, DOAC-treated patients had lower bleeding risk (HR, 0.562; 95% CI, 0.393-0.805; P = 0.002). The individual DOAC drugs did not differ significantly in terms of composite outcomes, recurrence, or bleeding events. Conclusion: DOAC showed comparable outcomes with warfarin in the fragile patient population.