Decreased Bleeding Incidence with Direct Oral Anticoagulants Compared to Vitamin K Antagonist and Low-Molecular-Weight Heparin in Patients with Sickle Cell Disease and Venous Thromboembolism

Background: Venous thromboembolism (VTE) is a recognized complication of sickle cell disease (SCD), yet the optimal pharmacologic anticoagulant is unknown. Methods: A retrospective single-institution cohort study of patients with SCD complicated by first VTE from January 2009 through July 2017 was performed using ICD 9/10 codes. Data collected included the anticoagulant used, VTE recurrence, and incidence of bleeding. Results: 109 patients with VTE were identified. SCD genotypes included HbSS in 92 (84%), HbSC in 13 (12%), and HbS-β+ thalassemia in 4 (4%). After the initial VTE event, 32 patients received a vitamin K antagonist (VKA), 34 for low-molecular-weight heparin (LMWH), and 43 for direct oral anticoagulants (DOACs). 16 patients (15%) experienced a clinically significant bleeding event, including 9 on VKA, 5 on LMWH, and 2 on DOACs. At a median follow-up of 11.8 (range, 3.4-60) months, 33 patients had a recurrent VTE, including 10 on VKA, 10 on LMWH, and 13 on DOACs (p = 0.833). Bleeding incidence was least with the DOACs, which were associated with fewer bleeding events (OR 0.22), and greatest with VKA (OR 1.55) (p < 0.05). Conclusion: There was no difference between VTE recurrence and choice of anticoagulation in SCD patients with VTE. Bleeding events were lower for DOACs compared to VKA or LMWH.