Abstract 157: Association Of Hospital Performance With 1-Year Mortality And Recurrence After Ischemic Stroke Among US Medicare Beneficiaries

Abstract

Background: Whether stroke patients treated at hospitals with better short-term quality performance metrics have better long-term outcomes is unknown. We determined if ischemic stroke patients treated at US hospitals with better past performance on the Centers for Medicare & Medicaid Services (CMS) 30-day mortality and readmission outcome measures for stroke had better 1-year outcomes compared to those treated at other hospitals. Methods: We included all Medicare fee-for-service beneficiaries aged ≥65 years discharged alive from US hospitals with a principal diagnosis of ischemic stroke from 07/01/2015 to 12/31/2018. We categorized patients by the treating hospital’s performance on the CMS hospital-specific 30-day risk-standardized all-cause mortality and readmission rate measures for stroke from 07/01/2012 to 06/30/2015: Low-Low (both CMS mortality and readmission rates for the hospital were <25 th percentile of national rates), High-High (both >75 th percentile), and Intermediate (all others). We balanced characteristics between hospital performance categories using stabilized inverse probability weights (IPW) based on patient demographic and clinical factors. We fit Cox models to assess patient risks of 1-year mortality and recurrent stroke across hospital performance categories, weighted by the IPW and accounting for competing risks. Results: There were 595,929 stroke patients (mean age 78.9y, 54.4% women, 82.2% White) discharged from 134 Low-Low, 2288 Intermediate, and 141 High-High hospitals. For patients treated at Low-Low, Intermediate, and High-High hospitals, respectively, 1-year mortality rates were 23.8% (95% CI 23.3-24.3%), 25.2% (25.1-25.3%), and 26.5% (26.1-26.9%), and recurrence rates were 8.0% (7.6-8.3%), 7.9% (7.8-8.0%), and 8.0% (7.7-8.3%). Compared with patients at High-High hospitals, those at Low-Low and Intermediate hospitals, respectively, had 15% (hazard ratio 0.85; 95% CI 0.82-0.87) and 9% (0.91; 0.89-0.93) lower risks of 1-year mortality but no difference in 1-year recurrence. Conclusions: Ischemic stroke patients treated at better-performing hospitals had lower risks of post-discharge 1-year mortality but similar risks of recurrent stroke compared with patients treated at other hospitals.