Abstract 35: 30-Day Risk-Standardized Mortality and Readmission after Ischemic Stroke in Critical Access Hospitals

Abstract

Background: Critical access hospital (CAH) designation identifies hospitals providing emergency and inpatient care to residents of rural communities. Patients with cardiovascular disease and pneumonia have poorer outcomes at CAHs, but stroke outcomes have not been assessed. Objective: Compare risk-adjusted 30-day mortality and readmission rates after ischemic stroke for patients treated at critical access and non-critical access hospitals. Methods: The cohort included all fee-for-service Medicare beneficiaries 65+ years of age discharged with a primary diagnosis of ischemic stroke (ICD-9 433, 434, 436) in 2006. Risk-standardized mortality and readmission rates at 30 days were compared for patients treated at CAH versus other hospitals using hierarchical logistic regression models, adjusted for patient demographics, medical history, and comorbid conditions. Results: There were 10,267 ischemic stroke discharges from 1,165 CAHs and 300,114 discharges from 3,381 non-CAHs. Patients discharged from CAHs were older, more often women and white, and generally had more comorbid conditions. CAHs had higher unadjusted in-hospital (6.4% vs. 4.6%, p<0.001) and 30-day (19.9% vs. 10.9%, p<0.001) mortality rates than non-CAHs, but lower 30-day all-cause readmission (12.4% vs. 13.8%, p<0.001). In risk-standardized analyses, the differences were less marked for 30-day mortality (CAHs vs. non-CAHs; 11.9%±1.4% vs. 10.9%±1.7%, p<0.001), with no difference in 30-day readmission (13.7%±0.6% vs. 13.7%±1.4%, p=0.2787). Conclusions: Although there were no differences in readmission rates, stroke patients discharged from CAHs had higher unadjusted mortality than those discharged from non-CAHs. These differences, however, were at least partially explained by differences in patient characteristics. Further research is needed to identify factors contributing to these differences.