Endovascular Treatment Decision Making in Octogenarians and Nonagenarians : Insights from UNMASK EVT an International Multidisciplinary Study

Background: Evidence for efficacy and safety in stroke patients ≥80 years is limited, since they were underrepresented in randomized thrombectomy trials. This study sought to explore how physicians approach endovascular therapy (EVT) decision making in octogenarians and nonagenarians under their current local resources under assumed ideal conditions, i.e. without external (monetary or infrastructural) limitations. Methods: In an international multidisciplinary survey, 607 physicians involved in acute stroke care were randomly assigned 10 out of a pool of 22 case scenarios with different evidence levels for EVT, 4 of which involved octogenarians and 2 nonagenarians, and asked how they would treat the patient in the given scenario A) under their current local resources and B) under assumed ideal conditions, i.e. with no external restraints. Decision rates were calculated and clustered multivariable regression analysis performed to determine adjusted measures of effect size for patient age. Results: In octogenarians, physicians decided in favor of EVT in 76.7% (all of which were level 2B evidence scenarios) under current local resources and in 80.2% under assumed ideal conditions. In nonagenarians, 74.0% decided in favor of EVT under current local resources (level 1A scenarios: 87.7%, level 2B scenarios: 60.3%) and 79.2% would offer EVT under assumed ideal conditions (level 1A scenarios: 91.3%, level 2B scenarios: 67.2%). Age was not a significant predictor for treatment decision under current local resources (adjusted odds ratio, OR: 0.99, confidence interval, CI: 0.96-1.02 per decile increase) and under assumed ideal conditions (adjusted OR: 1.00, CI 0.97-1.03 per decile increase). Conclusion: The vast majority of physicians participating in this survey would offer EVT to acute ischemic stroke patients above 80 years.restrictio