Return on Investment of the Endovascular Therapy Within 6–24 h Treatment Window in Alberta, Canada

INTRODUCTION: In preparation for a planned change of Emergency Medical Services triaging of suspected stroke dispatch in Alberta, we conducted a modeling exercise to predict the return on investment (ROI) of switching from the current endovascular thrombectomy (EVT) within a 6 h window to a 24 h window. METHODS: Using the Alberta Health Services administrative databases, we estimated the health service utilization (HSU) (including inpatient, outpatient, physician services and prescription drugs) cost of patients with stroke treated with EVT24h following the case-mix group plus methodology. The impact of EVT on HSU cost avoidance (B) and the cost (C) of EVT24h implementation were estimated, including costs for EVT procedure, diagnostic imaging and ambulance for all suspected strokes. Finally, ROI was calculated as the benefit divided by the cost (ROI = B/C). Threshold, deterministic and probabilistic sensitivity analyses were performed. RESULTS: There were 288 patients treated with EVT24h between 2021/22 and 2023/24. The HSU cost per patient in the year following EVT treatment was estimated at $92,201. Given the impact of EVT was 30%, the benefit of EVT was estimated at $39,515. The cost of EVT24h implementation was $24,358 per EVT patient. Accordingly, ROI was estimated at 1.6 (ranged 0.7-2.0), and cost avoidance per patient was $15,157 (ranged - $8013 to $25,362). Given that there were 96 EVT24h per year, the cost avoidance for the health system would be $1.5 million annually. The probabilistic sensitivity analysis showed that the probability for EVT24h to be cost-avoidable (or ROI > 1) was 88.5%. CONCLUSION: The expansion of EVT from 6 to 24 h is expected to result in a positive ROI.