Prescribing patterns of apixaban and rivaroxaban for extended-phase anticoagulant therapy

Reduced-dose apixaban or rivaroxaban has been suggested for extended-phase anticoagulant therapy for prevention of venous thromboembolism (VTE). The uptake of this suggestion in clinical practice is unclear. The purpose of this study was to describe the prescribing patterns of apixaban and rivaroxaban for extended-phase anticoagulant therapy in an urban university setting.

This was a retrospective, single-center, observational study in patients 18 years of age or older with a history of VTE that occurred at least 6 months prior. Patients prescribed rivaroxaban or apixaban from December 2, 2021, until June 1, 2022, were included. Pregnant women and patients on apixaban or rivaroxaban for indications other than VTE were excluded. The primary outcome was the proportion of patients on reduced-dose vs full-dose apixaban or rivaroxaban. The secondary outcome was the presence of patient-specific characteristics that were more common in patients on reduced-dose vs full-dose anticoagulant.

Of the 287 patients who met the eligibility criteria, 214 (74.6%) were prescribed full-dose apixaban or rivaroxaban and 73 (25.4%) were prescribed reduced-dose apixaban or rivaroxaban. Sickle cell disease was more common in patients prescribed full-dose anticoagulant (14.5% vs 2.7%; P = 0.01), and stage 5 chronic kidney disease was more common in patients prescribed reduced-dose anticoagulant (3.3% vs 11%; P = 0.01). Prescribers specialized in hematology/oncology were more likely to prescribe reduced-dose than full-dose anticoagulant (37.0% vs 22.4% of all prescriptions; P = 0.01).

The majority of patients were prescribed full-dose rivaroxaban or apixaban for extended-phase anticoagulation, despite guidance suggesting use of a reduced dose. Prescribers may consider patient-specific risks for thrombosis and bleeding when selecting a dose of apixaban or rivaroxaban for VTE prevention.