Cost-effectiveness of oral anticoagulant therapy in patients with device-detected atrial fibrillation
A K Winsten, V Langen, K E J Airaksinen, K TeppoAbstract
Background
The role of anticoagulation for stroke prevention in patients with device-detected atrial high-rate episodes, also known as subclinical atrial fibrillation (AF), remains a subject of equipoise. The two trials on this subject have shown somewhat inconclusive results and subsequent modelling studies have suggested that the net benefit of anticoagulant therapy in these patients is minimal and uncertain.
Purpose
To evaluate whether direct oral anticoagulant (DOAC) therapy in patients with device-detected AF is cost-effective from healthcare perspective.
Methods
A previously published Markov model was updated to address the question of cost-effectiveness, which was measured as incremental QALYs, costs, and the incremental cost-effectiveness ratio (ICER; cost per QALY gained) for initiating DOAC therapy compared with no treatment per patient. The model incorporated trial-based evidence on the effects of anticoagulation on rates of stroke, bleeding, and mortality, accounting for the number and severity of ischemic and hemorrhagic strokes, other intracranial and extracranial bleeds, and deaths, as well as their impact on quality of life over a 10-year simulation period in 10 000 patients with subclinical AF. In the current model, healthcare costs related to these clinical outcomes and DOAC therapy (€50/month) were added, derived from recently published Nordic healthcare data. A 3% discount rate was utilized to both costs and QALYs. Cost-effectiveness was compared against a willingness-to-pay threshold of €50 000/QALY. Probabilistic sensitivity analyses with 2 000 iterations of sampled treatment effects for stroke and bleeding from a log-normal distribution were performed. Exploratory analyses were conducted by CHA2DS2-VASc category (<4, 4, >4). We also varied DOAC costs to assess their impact on the results.
Results
The decision to start DOACs resulted in five quality-adjusted days of life (0.015 QALYs) and €2 534 higher costs per patient, resulting in an ICER of €163 761. In probabilistic sensitivity analyses, DOAC therapy was cost-effective in 3% of simulations and dominated in 88% (Figure). Varying monthly DOAC costs from €30 to €70 resulted in ICERs of €61 258 and €266 264, respectively. Decision to start DOACs was dominated at CHA2DS2-VASc scores <4 and 4, but dominant at scores >4.
Conclusion
Routine DOAC therapy for all patients with device-detected AF is unlikely to be cost-effective, but it may be cost-effective in those with a CHA2DS2-VASc score >4.Probabilistic Sensitivity Analysis