Estimating the Effectiveness and Cost-effectiveness of Establishing Additional Endovascular Thrombectomy Stroke Centres in England: a Discrete Event Simulation

Background: We have previously modelled that the optimal number of comprehensive stroke centres (CSC) providing endovascular thrombectomy (EVT) in England would be 30 (net 6 new centres). We now estimate the relative effectiveness and cost-effectiveness of increasing the number of centres from 24 to 30.

Methods: We constructed a discrete event simulation (DES) to estimate the effectiveness and lifetime cost-effectiveness (from a payer perspective) using 1 year's incidence of stroke in England. 2000 iterations of the simulation were performed comparing baseline 24 centres to 30.

Results: Of 80,800 patients admitted to hospital with acute stroke/year, 21,740 would be affected by the service reconfiguration. The median time to treatment for eligible early presenters (< 270 min since onset) would reduce from 195 (IQR 155-249) to 165 (IQR 105-224) minutes. Our model predicts reconfiguration would mean an additional 33 independent patients (modified Rankin scale [mRS] 0-1) and 30 fewer dependent/dead patients (mRS 3-6) per year. The net addition of 6 centres generates 190 QALYs (95%CI - 6 to 399) and results in net savings to the healthcare system of £1,864,000/year (95% CI -1,204,000 to £5,017,000). The estimated budget impact was a saving of £980,000 in year 1 and £7.07 million in years 2 to 5.

Conclusion: Changes in acute stroke service configuration will produce clinical and cost benefits when the time taken for patients to receive treatment is reduced. Benefits are highly likely to be cost saving over 5 years before any capital investment above £8 million is required.