MO4 Economic Evaluation of Treatment Strategies for Late-Presentation Acute Ischemic Stroke

Abstract

Nam J, O’Reilly D PATH Research Institute, McMaster University, Hamilton, ON, Canada OBJECTIVES: For late-presentation ischemic stroke patients, economic evidence comparing all currently employed treatment strategies is lacking. We conducted an economic evaluation comparing best medical treatment to intravenous thrombolysis, intra-arterial thrombolysis and mechanical thrombectomy for these patients. METHODS: A probabilistic economic model was designed from the perspective of a government payer to calculate the lifetime incremental costs and quality adjusted life years (QALYs) for each treatment compared to best medical treatment. Effectiveness data were extracted from randomized trials, where possible, and discharge disposition from Ontario stroke registries. Inpatient costs were taken from the Ontario Case Costing Initiative, professional fees from the Ontario Schedule of Benefits for Physician Services and other costs from an Ontario cost of stroke study. Costs were presented in 2011 Canadian dollars. RESULTS: Expected incremental QALYs over best medical treatment were 0.02, 0.16 and 0.27 for intravenous thrombolysis, intra-arterial thrombolysis and mechanical thrombectomy, respectively, while the expected incremental costs were $1,986; $4,336 and $4,058, respectively. Expected incremental QALYs and costs showed that both intravenous thrombolysis and intra-arterial thrombolysis were extendedly dominated. Mechanical thrombectomy had an incremental cost-effectiveness ratio of $14,790/ QALY. At a willingness-to-pay threshold of $50,000/QALY, mechanical thrombectomy and intra-arterial thrombolysis had 70% and 30% likelihood of being costeffective, respectively. Intravenous thrombolysis had the lowest probability of being cost-effective across all willingness-to-pay thresholds ($0-$200,000/QALY). CONCLUSIONS: Intravenous thrombolysis in late-presentation stroke patients may not be a cost-effective treatment strategy. Endovascular approaches such as intra-arterial thrombolysis and especially mechanical thrombectomy may lead to an economic benefit, though more evidence is needed to reduce considerable decision uncertainty.