Stroke and systemic embolism prevention in patients with atrial fibrillation in Belgium: comparative cost effectiveness of new oral anticoagulants and warfarin.

BACKGROUND AND OBJECTIVE: Management of non-valvular atrial fibrillation (NVAF) focuses on the use of anticoagulation to mitigate the risk of stroke. Until recently, vitamin K antagonist (VKA) treatment was considered the standard of care, with the emergence of non-VKA oral anticoagulants (NOACs) shifting treatment practice. The objective of this study was therefore to assess the use of warfarin and the NOACs for stroke prevention in patients with NVAF from the perspective of a Belgian healthcare payer using a cost-effectiveness analysis and the efficiency frontier approach.

METHODS: A previously published Markov model was adapted to the Belgian healthcare setting. Clinical events modelled include ischaemic and haemorrhagic stroke, systemic embolism, intracranial haemorrhage, other major bleeding, clinically relevant non-major bleeding, myocardial infarction, cardiovascular hospitalisation and treatment discontinuations. Efficacy and bleeding data for warfarin and apixaban 5 mg twice daily were obtained from the ARISTOTLE trial, whilst those for other NOACs (rivaroxaban 20 mg once daily, dabigatran 110 mg twice daily, dabigatran 150 mg twice daily) were from published indirect comparisons. Acute medical costs were obtained from reimbursement payments made to Belgian hospitals, whilst long-term medical costs and utility data were derived from the literature. The efficiency frontier was calculated using total costs and quality-adjusted life-years (QALYs) as outcomes. Univariate and probabilistic sensitivity analyses were performed.

RESULTS: Warfarin and apixaban were the two optimal treatment choices, as the other three treatment alternatives including dabigatran 110 mg, dabigatran 150 mg switching to dabigatran 110 mg at the age of 80 years and rivaroxaban were extendedly or strictly dominated on the efficiency frontier. Apixaban was a cost-effective alternative vs warfarin at an incremental cost-effectiveness ratio of <euro>7,212/QALY gained.

CONCLUSIONS: Amongst NOACs, apixaban may be the most economically efficient alternative to warfarin in NVAF patients who are suitable for VKA treatment and eligible for stroke prevention in Belgium.