Low-dose direct oral anticoagulants for secondary prevention in patients at high risk for recurrence due to history of recurrent venous thromboembolic events or severe thrombophilia: a retrospective analysis of the Italian Survey on anTicoagulated pAtients RegisTry 2

Background Long-term anticoagulation is recommended in patients with venous thromboembolism (VTE) deemed at high risk for recurrence (HRR). Limited information is available on patients with recurrent VTE and/or severe thrombophilia. In addition, these patients were not included in studies evaluating long-term treatment with low doses of direct oral anticoagulants (DOACs). Objectives The aims of our study were to (1) record the drugs and dosages used in HRR patients, and (2) to record adverse events occurring during follow-up. Methods Among 2520 VTE patients enrolled in the Survey on anTicoagulated pAtients RegisTry 2, we retrospectively analyzed the management of patients with a history of recurrent VTE and/or severe thrombophilia (HRR patients). Results A total of 487 HRR patients were analyzed. Anticoagulants were stopped in 11 of 487 patients (2.3%), full-dose DOACs were continued in 176 patients (36.1%), and 311 patients (63.9%) were shifted to low-dose DOACs (61.4% with apixaban 2.5 mg twice a day and 38.6% with rivaroxaban 10 mg once a day) after a median time of 1.3 years (range, 0.5-20.2 years). During follow-up, no adverse events were recorded in patients who stopped treatment. Among patients who continued treatment, 10 had recurrent VTE (rate, 0.4 × 100 patient-years) and 19 had bleeding (rate, 0.9 × 100 patient-years). The risk of recurrent VTE was similar between patients on full-dose and low-dose anticoagulation. Patients on full-dose anticoagulation had a trend toward a higher bleeding risk (relative risk, 2.2; 95% CI, 0.7-9.0). Conclusion HRR patients with a history of unprovoked recurrent VTE and/or patients with severe thrombophilia treated with long-term low-dose DOACs showed a low risk for recurrence and bleeding events. © 2025 International Society on Thrombosis and Haemostasis.