Hospital Readmission Following Discharge From Inpatient Rehabilitation for Older Adults With Debility.

Abstract

Debility accounts for 10% of inpatient rehabilitation cases among Medicare beneficiaries. Debility has the highest 30-day readmission rate among 6 impairment groups most commonly admitted to inpatient rehabilitation. The purpose of this study was to examine rates, temporal distribution, and factors associated with hospital readmission for patients with debility up to 90 days following discharge from inpatient rehabilitation. A retrospective cohort study was conducted using records for 45,424 Medicare fee-for-service beneficiaries with debility discharged to community from 1,199 facilities during 2006-2009. Cox proportional hazard regression models were used to estimate hazard ratios for readmission. Schoenfeld residuals were examined to identify covariate-time interactions. Factor-time interactions were included in the full model for Functional Independence Measure (FIM) discharge motor functional status, comorbidity tier, and chronic pulmonary disease. Most prevalent reasons for readmission were summarized by Medicare severity diagnosis related groups. Hospital readmission rates for patients with debility were 19% for 30 days and 34% for 90 days. The highest readmission count occurred on day 3 after discharge, and 56% of readmissions occurred within 30 days. A higher FIM discharge motor rating was associated with lower hazard for readmissions prior to 60 days (30-day hazard ratio=0.987; 95% confidence interval=0.986, 0.989). Comorbidities with hazard ratios >1.0 included comorbidity tier and 11 Elixhauser conditions, 3 of which (heart failure, renal failure, and chronic pulmonary disease) were among the most prevalent reasons for readmission. Analysis of Medicare data permitted only use of variables reported for administrative purposes. Comorbidity data were analyzed only for inpatient diagnoses. One-third of patients were readmitted to acute hospitals within 90 days following rehabilitation for debility. Protective effect of greater motor function was diminished by 60 days after discharge from inpatient rehabilitation.