MODELLING DISABILITY-LEVEL AND UTILITY OUTCOMES DEPENDING ON TIME TO THROMBOLYSIS AND MECHANICAL THROMBECTOMY

Background: Hyper-acute stroke care requires the national coverage of thrombolysis (IVT) and thrombectomy (MT). In the UK, IVT is provided in all emergency stroke units, but MT is provided in fewer regional centres often requiring secondary transfer. Patients may gain more rapid access to IVT by using local IVT-only units, but at the expense of delayed access to MT. Optimal configuration of stroke services, comparison between 'drip-and-ship' and 'mothership' configurations and the population benefit from bypass models of pre-hospital care could be guided by a model that predicts outcomes based on times to IVT and MT.

Methods: We have synthesized clinical trial and five-year national stroke registry data to develop a disability-level outcome model and extended it to include utilities of resulting health states, that may be applied to analysis of organization of stroke services, and applied it to England and Wales.

Results: We have produced a mathematical model of stroke outcome (available at https://samuel-book.github.io/stroke_outcome/), and have made this available to other healthcare systems as a Python package (see https://pypi.org/project/stroke-outcome/). Illustrative output of the disability and utility benefits from differing access to IVT and MT are shown below:

Conclusions: A disability-level model of stroke outcome, with resultant utility values, based on times to IVT and/or MT has been developed, and made freely available. This has potential to guide the configuration of hyper-acute stroke care, particularly in systems like the UK with limited access to centres offering MT for which most patients require secondary transfer