title: Comparing Comorbidity Indices to Predict Post-Acute Rehabilitation Outcomes in Older Adults.
abstract: Compare 5 comorbidity indices to predict community discharge and functional status following post-acute rehabilitation.
  
  
  
  This was a retrospective study of Medicare beneficiaries with stroke, lower-extremity fracture, and joint replacement discharged from inpatient rehabilitation in 2011 (N = 105,275). Community discharge and self-care, mobility, and cognitive function were compared using the Charlson, Elixhauser, Tier, Functional Comorbidity, and Hierarchical Condition Category comorbidity indices.
  
  
  
  Of the patients, 64.4% were female, and 84.6% were non-Hispanic white. Mean age was 79.3 (SD, 7.5) years. Base regression models including sociodemographic and clinical variables explained 56.6%, 42.2%, and 23.0% of the variance (R) for discharge self-care; 47.4%, 30.9%, and 18.6% for mobility; and 62.0%, 55.3%, and 37.3% for cognition across the 3 impairment groups. R values for self-care, mobility, and cognition increased by 0.2% to 3.3% when the comorbidity indices were added to the models. The base model C statistics for community discharge were 0.58 (stroke), 0.61 (fracture), and 0.62 (joint replacement). The C statistics increased more than 25% with the addition of discharge functional status to the base model. Adding the comorbidity indices individually to the base model resulted in C-statistic increases of 1% to 2%.
  
  
  
  Comorbidity indices were poor predictors of community discharge and functional status in Medicare beneficiaries receiving inpatient rehabilitation.
authors.affiliation: From the Division of Rehabilitation Sciences (AK, JEG, AMK, KJO) and Institute for Translational Sciences (AT, KJO), University of Texas Medical Branch, Galveston, Texas; RTI International, Washington, DC (AD); Rehabilitation Institute of Chicago, Chicago, Illinois (AD); Department of Health Services, Policy and Practice, Brown University (LR); and Providence VA Medical Center (LR), Providence, Rhode Island.
authors.forename: Amit
authors.initials: A
authors.lastname: Kumar
authors.forename: James E
authors.initials: JE
authors.lastname: Graham
authors.forename: Linda
authors.initials: L
authors.lastname: Resnik
authors.forename: Amol M
authors.initials: AM
authors.lastname: Karmarkar
authors.forename: Alai
authors.initials: A
authors.lastname: Tan
authors.forename: Anne
authors.initials: A
authors.lastname: Deutsch
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Ottenbacher
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D019643:Arthroplasty, Replacement / Q000534:rehabilitation*; D015897:Comorbidity; D005260:Female; D050723:Fractures, Bone / Q000150:complications / Q000534:rehabilitation*; D006304:Health Status; D006760:Hospitalization; D006801:Humans; D008297:Male; D006278:Medicare; D011237:Predictive Value of Tests; D020127:Recovery of Function; D012189:Retrospective Studies; D000071939:Stroke Rehabilitation; D016896:Treatment Outcome; D014481:United States