Costs and health effects of CT perfusion-based selection for endovascular treatment of patients with a large vessel occlusion presenting within six hours after symptom onset: A model-based health economic evaluation

IntroductionCurrent stroke guidelines do not give uniform recommendations regarding the use of CT perfusion (CTP) for the selection of patients presenting within six hours after symptom onset for endovascular treatment (EVT). Model-based analyses can be used to estimate the potential long-term costs and health effects of CTP for patient selection. MethodsIn this nationwide retrospective cohort study with model-based health economic evaluation, 703 large vessel occlusion acute ischemic stroke patients with CTP imaging and EVT within six hours after symptom were included (Inclusion: January 2018-March 2022; trialsearch.who.int:NL7974). CTP-based EVT patient selection using varying ischemic core volumes (ICV) and core-penumbra mismatch ratios (MMR) was compared with providing EVT to all patients. Net monetary benefit (NMB) at a willingness to pay of {euro}80,000 per quality-adjusted life year, the incremental cost-effectiveness ratio (ICER), the difference in costs ({Delta}Costs), and quality-adjusted life years ({Delta}QALY) per 1000 patients were the outcome measures. ResultsThe cohort of patients with CTP and EVT used for simulations consisted of 391/703 males with a median age of 72 (IQR:62;81). Considering the most optimal ICV ([≥]110mL) and MMR ([≤]1.4) thresholds, CTP-based selection for EVT resulted in a loss of health ({Delta}QALYs: ICV-median:-3.3[IQR:-5.9;-1.1], MMR median:0.0 [IQR:-1.3;0.0]), limited additional costs or cost savings ({Delta}Costs: ICV-median:-{euro}348,966[IQR:-{euro}712,406;-{euro}51,158], MMR-median:{euro}266,336[IQR:{euro}229,403;{euro}380,095]), and an ICER and NMB with a wide IQR (ICER ICV-median:71,346[IQR:-16,517;181,241], MMR-median:312,955[IQR:-141,379;infinite]) (NMB ICV-median:{euro}102,227[IQR:-{euro}282,942;{euro}431,923], MMR-median:-{euro}278,850[IQR:-{euro}457,097:-{euro}229,403]). ConclusionIn EVT-eligible patients presenting within six hours after symptom onset, excluding patients based on CTP parameters was not cost-effective and could potentially harm patients. Key pointsO_ST_ABSWhat is already known on this topicC_ST_ABSRecent randomized clinical trials in patients with a large vessel occlusion and a large infarct region concluded that endovascular treatment (EVT) resulted in more favorable patient outcomes compared to best medical management. However, it remains largely unclear what the associated costs and health implications are in the long run of CT perfusion (CTP) based patient selection for EVT in patients presenting within six hours after symptom onset. What this study addsAt optimized ischemic core volume (ICV) and core-penumbra mismatch ratio (MMR) thresholds, CTP-based selection for EVT resulted in a loss of health ({Delta}QALYs: ICV[≥]110mL median:-3.3[IQR:-5.9;-1.1], MMR[≤]1.4 median:0.0 [IQR:-1.3;0.0]) for similar costs ({Delta}Costs: ICV[≥]110mL median:-{euro}348,966[IQR:-{euro}712,406;-{euro}51,158], MMR[≤]1.4 median:{euro}266,336[IQR:{euro}229,403;{euro}380,095]) per 1,000 patients. How this study might affect research, practice or policySelecting patients using CTP will likely result in a loss of health and at best a minor cost saving. Even in scenarios considering unfeasibly low EVT benefit and in patients aged[≥]80 years CTP based patient selection for EVT was not cost-effective.