Abstract WP104: Updating Cost-Effectiveness of Stroke Thrombectomy in Patients With Large Core Ischemic Stroke Using 2023 Clinical Trial Data

Abstract

Introduction: Stroke thrombectomy (ST) is cost-effective for acute ischemic stroke (AIS) patients with large-vessel occlusion and low Alberta Stroke Program Early CT Score (ASPECTS <6) compared with non-endovascular standard care (SC). However, previous cost-effectiveness analyses (CA) were based on data that were not specific to low ASPECTS or had limited generalizability (e.g., data on Japanese patients with ASPECTS 3-5). As new results from two 2023 clinical trials that included patients with ASPECTS <6 emerged from Western countries and China, we aim to update the cost-effectiveness of ST using new data from different populations and assess how ST treatment delay might affect the comparative effectiveness of ST and SC. Methods: We updated the cost-effectiveness of ST compared with SC in AIS patients aged 67 years with ASPECTS <6 based on the data from two trials conducted in Western countries and China using a previously published Markov model that simulates the lifetime cost and quality-adjusted life years (QALYs) with annual cycles. The difference between ST and SC was characterized by the patient distribution of modified Rankin Scales at 90 days after hospital discharge (90-day mRS) as reported from the two trials. We conducted two separate CA at a willingness-to-pay threshold of $100,000/QALY using the 90-day mRS distribution from each trial with the ST treatment delay as observed in the trials (base case). In addition, we assessed how the effectiveness of ST varied with ST treatment delay up to 6 hours in addition to the observed delay in trials. Results: In the base case, irrespective of two trial datasets, ST is a dominant strategy that saved $8,431-$32,083 and nearly 1 QALY with a positive net monetary benefit (NMB) compared to SC, which had a negative NMB. Regarding ST treatment delay, the QALYs generated from ST decreased as additional treatment delay increased. If the additional ST treatment delay was within 2-3.5 hours, ST could generate more QALYs and was still cost-effective compared to SC. Conclusions: Our findings suggest ST is the preferred strategy over SC in AIS patients with low ASPECTS. ST remains effective and cost-effective even when ST is delayed beyond the median transfer time of 174 minutes in the U.S. reported in Stamm et al. JAMA study.