Warfarin versus direct oral anticoagulants for patients needing distal deep vein thrombosis treatment

Objective: Great interest exists in standardizing the anticoagulant choice for patients requiring treatment of distal deep vein thrombosis (DDVT). In the present multicenter, retrospective cohort study, we evaluated the outcomes of patients with DDVT who had been treated with warfarin vs direct oral anticoagulants (DOACs; ie, rivaroxaban, apixaban, edoxaban, dabigatran). Methods: Queries were built for the TriNetX database (TriNetX LLC, Cambridge, Mass), a federated network of healthcare organizations across the United States that provides de-identified patient data through aggregated counts and statistical summaries. International Classification of Diseases, 10th revision, diagnostic codes were used to identify eligible patients. Data from January 1, 2013 to January 1, 2020 were reviewed. Statistical analyses, including propensity matching, were performed using TriNetX's internal software. The inclusion criterion was treatment with either warfarin or a DOAC started within the first 24 hours of diagnosis of an isolated thrombosis of the following veins: anterior tibial, posterior tibial, peroneal, or calf muscular veins. The exclusion criteria were a history of an adverse reaction to anticoagulant agents, SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection, thrombophilia, mechanical heart valve, chronic proximal DVT (PDVT) and/or DDVT, and 6-month history of the following: acute PDVT, pulmonary embolism (PE), or anticoagulant usage. The outcomes measured included the incidence of mortality, PE, PDVT, stroke, myocardial infarction, and major bleeding within 6 months after initiating anticoagulation therapy. Results: In a cohort of 6509 patients, 1570 were treated with warfarin and 4939 were treated with a DOAC drug. After propensity matching for age, sex, ethnicity, and comorbidities, the DOAC cohort had a significantly lower incidence of PE (1.795% vs 3.590%; P = .0020) and major bleeding (7.949% vs 10.513%; P = .0134). Differences in the incidence of mortality, PDVT, myocardial infarction, and stroke were not statistically significant. Conclusions: Before the present study, no strong evidence was available to suggest an optimal treatment modality for DDVT requiring anticoagulation therapy. The data from the present study suggest that patients receiving DOACs for the treatment of DDVT will have significantly lower rates of progression to PE and a lower incidence of major bleeding compared with patients receiving warfarin. This suggests that DOACs are superior to warfarin for treatment of DDVT.