Functional Status Across Post-Acute Settings is Associated With 30-Day and 90-Day Hospital Readmissions

Objective: To examine the association between cocalibrated functional scores across post-acute care settings and the subsequent risk of hospital readmission. Design: Retrospective cohort study. Setting and Participants: We analyzed 781,021 fee-for-service Medicare beneficiaries discharged to either inpatient rehabilitation facilities (IRFs), skilled nursing facilities (SNFs), or home health agencies (HHA) after an acute hospital stay for stroke (N = 143,277), lower extremity joint replacements (512,577), and hip/femur fracture (125,167) between January 1, 2013, and August 31, 2014. Measures: Functional items from IRF-PAI, MDS, and OASIS were categorized into self-care and mobility domains. We cocalibrated admission functional scores across post-acute settings and divided scores into 4 functional levels using quartiles (Q1-Q4, with Q4 representing the most independent function). The primary outcomes were 30-day and 90-day hospital readmissions (yes/no) after an initial post-acute stay. Results: Patients who were more dependent in self-care and mobility at the initial post-acute setting were significantly more likely to experience hospital readmission [eg, hazard ratios of 30-day readmission in stroke: 1.54 (95% confidence interval [CI] 1.47-1.61), 1.18 (95% CI 1.14-1.23), and 1.12 (95% CI 1.08-1.16) for Q1, Q2 and Q3, compared to Q4]. We found similar results for risk of 90-day hospital readmission across impairment conditions. Conclusions and Implications: Patients who were more functionally dependent at the initial post-acute setting had a higher risk to readmit to the hospitals after discharging from the post-acute setting for 30 and 90 days, compared with patients who were more functionally independent. This finding is consistent across impairment conditions and post-acute settings. Future research should determine effective strategies of maintaining and facilitating functional performance across post-acute settings to optimize long-term patient outcomes.