Abstract WP013: Associations Between Hospital Characteristics and Stroke Thrombectomy Outcomes in the United States

Endovascular thrombectomy (EVT) for large vessel occlusion (LVO) stroke is increasingly performed across diverse hospital settings, but the impact of hospital characteristics on patient outcomes remains unclear. Previous studies have shown a negative correlation between EVT volume and outcomes, while others paradoxically found better outcomes at lower-volume centers. Other hospital characteristics, such as teaching status and ownership structure may also impact EVT outcomes, though data are scarce. In this retrospective cohort study, we utilize the US Nationwide Readmissions Database (NRD) to examine the association between hospital characteristics and clinical outcomes following EVT for LVO stroke. Our primary hypothesis is that treatment at non-profit, high-volume teaching centers (NP-HVTCs) results in superior outcomes compared to treatment at other facilities. We identified adult patients who underwent EVT for LVO stroke using ICD-10-CM procedure codes within the NRD from 2016 to 2022. We defined NP-HVTCs as facilities with bed size ≥500, annual EVT volume ≥100, and metropolitan teaching hospital designation. The primary outcome was routine discharge home. Secondary outcomes included in-hospital mortality, intracranial hemorrhage (ICH), and non-ICH complications. Multivariable logistic regressions and causal mediation analyses were used to examine associations and mechanisms. A total of 101,247 EVT patients were identified with 17,444 (17.2%) treated at NP-HVTCs. NP-HVTC treatment was associated with higher rates of routine discharge (27.7% vs 22.9%; aOR 1.19 [95%CI 1.03–1.39], p=.021) and lower mortality (9.9% vs 13.4%; aOR 0.75 [95%CI 0.64–0.86], p<.001). NP-HVTCs also had lower rates of ICH (23.4% vs. 26.0%, aOR 0.88 [95%CI 0.81–0.96], p=0.006) and non-ICH complications (43.0% vs. 47.7%, aOR 0.92 [95%CI 0.85 to 1.01], p<.001), particularly respiratory complications (27.6% vs. 34.4%, aOR 0.73 [95%CI, 0.65–0.81], p<0.001). Mediation analyses showed that respiratory complications accounted for 34.5% of the association with routine discharge and 41.3% of the association with mortality (both p<0.001), whereas ICH explained <5% of the effect. Treatment at NP-HVTCs was associated with improved EVT outcomes, largely mediated by lower rates of respiratory complications. These findings highlight the importance of comprehensive perioperative and critical care in optimizing stroke outcomes and suggest avenues for quality improvement across hospital settings.