PURPOSE: The aim of this study was to understand the impact of oral anticoagulant (OAC) therapy on clinical outcomes and costs in patients with nonvalvular atrial fibrillation (NVAF) from a US Medicare perspective.
METHOD: A decision-analytic model was constructed to estimate the cost and outcomes associated with dabigatran compared with other NOACs (i.e., apixaban, edoxaban, and rivaroxaban) and warfarin for stroke risk reduction in adults with NVAF. Risks of clinical events were obtained from the published clinical trials. Costs were obtained from the published literature and standard US costing sources. Outcomes included nonfatal ischemic stroke, intracranial hemorrhage (ICH), major bleeding, minor bleeding, and vascular mortality. Drug and medical costs (in 2015 US dollars) and outcomes were estimated over a 5-year time horizon. One-way sensitivity analyses were conducted to examine the impact of various input parameters on total costs.
RESULT: Patients on NOACs experienced fewer nonfatal ischemic strokes (7.2, 8.3, 9.0, and 8.8 per 100 patients on dabigatran, apixaban, edoxaban, and rivaroxaban, respectively) and vascular deaths (9.7, 9.8, 10.1, and 10.1 per 100 patients on dabigatran, apixaban, edoxaban, and rivaroxaban, respectively) than patients on warfarin (9.4 nonfatal ischemic strokes and 11.2 vascular deaths per 100 patients). Dabigatran patients experienced fewer ICHs than all comparators in the study, and fewer major and minor bleeds than warfarin. Total per-patient costs over 5 years were $21,374 for warfarin and $27,892, $29,477, $28,468, and $30,897 for dabigatran, apixaban, edoxaban, and rivaroxaban, respectively. The NOACs had higher drug costs ($13,924, $13,958, $12,225, and $13,697 for dabigatran, apixaban, edoxaban, and rivaroxaban, respectively) but lower medical costs ($13,967, $15,519, $16,243, and $17,200, respectively) compared with warfarin ($3,849 drug, $17,525 medical). Results were most sensitive to risks and costs of nonfatal ischemic stroke and major bleeding.
CONCLUSION: Among all comparators in this study, dabigatran had the lowest incidence of nonfatal ischemic stroke, ICHs, and vascular deaths which resulted in lower medical costs.
