Cost-effectiveness of endovascular therapy for acute stroke with a large ischemic region in Japan: impact of the Alberta Stroke Program Early CT Score on cost-effectiveness

Background Although randomized clinical trials (RCTs) demonstrated short-term benefits of endovascular therapy (EVT) for acute ischemic stroke (AIS) with a large ischemic region, little is known about the long-term cost-effectiveness or its difference by the extent of the ischemic areas. We aimed to assess the cost-effectiveness of EVT for AIS involving a large ischemic region from the perspective of Japanese health insurance payers, and analyze it using the Alberta Stroke Program Early CT Score (ASPECTS). Methods The Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism-Japan Large Ischemic Core Trial (RESCUE-Japan LIMIT) was a RCT enrolling AIS patients with ASPECTS of 3–5 initially determined by the treating neurologist primarily using MRI. The hypothetical cohort and treatment efficacy were derived from the RESCUE-Japan LIMIT. Costs were calculated using the national health insurance tariff. We stratified the cohort into two subgroups based on ASPECTS of ≤3 and 4–5 as determined by the imaging committee, because heterogeneity was observed in treatment efficacy. EVT was considered cost-effective if the incremental cost-effectiveness ratio (ICER) was below the willingness-to-pay of 5 000 000 Japanese yen (JPY)/quality-adjusted life year (QALY). Results EVT was cost-effective among the RESCUE-Japan LIMIT population (ICER 4 826 911 JPY/QALY). The ICER among those with ASPECTS of ≤3 and 4–5 was 19 396 253 and 561 582 JPY/QALY, respectively. Conclusion EVT was cost-effective for patients with AIS involving a large ischemic region with ASPECTS of 3–5 initially determined by the treating neurologist in Japan. However, the ICER was over 5 000 000 JPY/QALY among those with an ASPECTS of ≤3 as determined by the imaging committee.