Abstract TP158: High Mortality In In-Hospital-Stroke Patients After Interhospital Transfer For Endovascular Therapy

There are only few studies examining In-Hospital-Stroke- (IHS) patients with a large vessel occlusion and subsequent transfer to a comprehensive stroke center for endovascular therapy (EVT). However, this patient group is highly relevant given the substantial amount of IHS, the ongoing trend towards a more frequent use of EVT and the lack of EVT capacities in rural hospitals. Furthermore, these patients are particularly vulnerable, as IHS is associated with higher rates of pre-existing conditions and worse clinical outcomes. We retrospectively analyzed prospectively collected data of patients receiving EVT after interhospital transfer from 15 rural hospitals of the Telemedical Stroke Network in Southeast Bavaria, Germany ( TEMPiS ) between 02-2018 and 07-2020. Baseline characteristics, treatment times and outcomes were compared between IHS- and Out-of-Hospital-Stroke- (OHS) patients. Primary endpoint was mRS after 3 months. A total of 49 IHS-patients and 274 OHS-patients received EVT after interhospital transfer. IHS-patients had a higher prevalence of atrial fibrillation (55.3% vs. 35.9%, p= 0.012), diabetes (36.2% vs. 21.1%, p= 0.024) and use of oral anticoagulants (44.7% vs. 20.8%, p< 0.001). Severity of stroke was similar in both groups. Treatment times from symptom onset to first brain imaging, therapy decision or groin puncture were significantly shorter for IHS-patients. IHS-patients displayed significantly worse outcomes: 59.2% of them died within 3 months compared to only 28.5% of OHS-patients (p< 0.001). Additionally, they were less likely to achieve moderate outcomes (mRS 0-3) 3 months after stroke (20.4% vs. 39.8%, p= 0.010). A logistic regression analysis revealed that - after controlling for possible confounding variables such as severity of stroke, premorbid state, pre-existing conditions, age and gender - IHS was significantly associated with a higher chance of death (adjusted OR: 3.99 (95%-CI: 1.84-8.92), p< 0.001). The mortality rate of IHS-patients who underwent EVT after interhospital transfer was substantially higher than that of OHS-patients. Thus, this patient group may not benefit from this therapeutic approach. In future studies alternative approaches that circumvent interhospital transfer should be explored.