Abstract 14258: Are Anticoagulants Necessary for Isolated Distal Deep Vein Thrombosis? From COMMAND VTE Registry 1 and 2

Abstract

Background: Anticoagulation for isolated distal deep vein thrombosis (DVT) remains controversial and is rarely recommended; however, all available data are from the warfarin era, and the effects of DOACs remain unknown. Objective and Methods: A large cohort of patients with acute venous thrombosis in the Contemporary Management and Outcomes in Patients with Venous Thromboembolism Registry (COMMAND VTE Registry 1 and 2) in Japan were included for analysis. We then evaluated the patient characteristics, clinical outcomes of symptomatic isolated distal DVT, and the risk-benefit of anticoagulation therapy by comparing direct oral anticoagulant (DOAC) and warfarin. Results: From a total of 8224 patients in the COMMAND registry, we excluded those with isolated distal DVT who had an event within 30 days of the initial venous thrombosis, leaving 1054 patients for the study. Among the 1054 patients included, 599, 312 and 143 were on DOACs, warfarin and no anticoagulant respectively. Overall, Kaplan-Meier analysis during a median follow-up of 988 days showed that anticoagulation significantly prevented recurrent VTE (P = 0.011), with no difference between warfarin and DOACs (P = 0.862). No clear increase in bleeding events were observed regardless of anticoagulation status (P = 0.327). Subsequent analysis stratified entries into transient (N = 318), Persistent (N = 353), and Unprovoked (N = 383) groups according to risk of venous thrombosis. In the persistent group, anticoagulation significantly prevented recurrent VTE (P = 0.025), with no difference between DOAC and warfarin (P = 0.939). In the transient group, anticoagulation was not effective in preventing recurrent VTE, with warfarin use significantly increasing bleeding events compared to those with DOAC or no anticoagulation (P = 0.030). Multivariate analysis showed that anticoagulation was independently associated with decreased incidence of venous thrombosis in the persistent group [HR: 0.262 (0.094-0.727), P = 0.010]. Conclusion: In symptomatic isolated distal DVT, anticoagulation is effective in preventing exacerbation of venous thrombosis; however, warfarin may increase bleeding events among the patients with transient DVT risk.