Amit Kumar1, James E Graham2, Linda Resnik3, Amol M Karmarkar4, Anne Deutsch5, Alai Tan6, Soham Al Snih7, Kenneth J Ottenbacher8. 1. A. Kumar, PT, MPH, PhD, Division of Rehabilitation Sciences, University of Texas Medical Branch, 301 University Blvd, Rte 1137, Galveston, TX 77555-1137 (USA). amkumar@utmb.edu. 2. J.E. Graham, PhD, DC, Division of Rehabilitation Sciences, University of Texas Medical Branch. 3. L. Resnik, PT, PhD, Department of Health Services, Policy and Practice, Brown University, Providence, Rhode Island, and Providence VA Medical Center, Providence, Rhode Island. 4. A.M. Karmarkar, PhD, MPH, Division of Rehabilitation Sciences, University of Texas Medical Branch. 5. A. Deutsch, RN, PhD, CRRN, RTI International, Washington, DC, and Rehabilitation Institute of Chicago, Chicago, Illinois. 6. A. Tan, MD, PhD, Institute for Translational Sciences, University of Texas Medical Branch. 7. S. Al Snih, MD, PhD, Division of Rehabilitation Sciences, University of Texas Medical Branch, and Sealy Center on Aging, University of Texas Medical Branch. 8. K.J. Ottenbacher, PhD, OTR, Division of Rehabilitation Sciences, University of Texas Medical Branch, and Sealy Center on Aging, University of Texas Medical Branch.
Abstract
BACKGROUND: Medicare data from acute hospitals do not contain information on functional status. This lack of information limits the ability to conduct rehabilitation-related health services research. OBJECTIVE: The purpose of this study was to examine the associations between 5 comorbidity indexes derived from acute care claims data and functional status assessed at admission to an inpatient rehabilitation facility (IRF). Comorbidity indexes included tier comorbidity, Functional Comorbidity Index (FCI), Charlson Comorbidity Index, Elixhauser Comorbidity Index, and Hierarchical Condition Category (HCC). DESIGN: This was a retrospective cohort study. METHODS: Medicare beneficiaries with stroke, lower extremity joint replacement, and lower extremity fracture discharged to an IRF in 2011 were studied (N=105,441). Data from the beneficiary summary file, Medicare Provider Analysis and Review (MedPAR) file, and Inpatient Rehabilitation Facility-Patient Assessment Instrument (IRF-PAI) file were linked. Inpatient rehabilitation facility admission functional status was used as a proxy for acute hospital discharge functional status. Separate linear regression models for each impairment group were developed to assess the relationships between the comorbidity indexes and functional status. Base models included age, sex, race/ethnicity, disability, dual eligibility, and length of stay. Subsequent models included individual comorbidity indexes. Values of variance explained (R(2)) with each comorbidity index were compared. RESULTS: Base models explained 7.7% of the variance in motor function ratings for stroke, 3.8% for joint replacement, and 7.3% for fracture. The R(2) increased marginally when comorbidity indexes were added to base models for stroke, joint replacement, and fracture: Charlson Comorbidity Index (0.4%, 0.5%, 0.3%), tier comorbidity (0.2%, 0.6%, 0.5%), FCI (0.4%, 1.2%, 1.6%), Elixhauser Comorbidity Index (1.2%, 1.9%, 3.5%), and HCC (2.2%, 2.1%, 2.8%). LIMITATION: Patients from 3 impairment categories were included in the sample. CONCLUSIONS: The 5 comorbidity indexes contributed little to predicting functional status. The indexes examined were not useful as proxies for functional status in the acute settings studied.
BACKGROUND: Medicare data from acute hospitals do not contain information on functional status. This lack of information limits the ability to conduct rehabilitation-related health services research. OBJECTIVE: The purpose of this study was to examine the associations between 5 comorbidity indexes derived from acute care claims data and functional status assessed at admission to an inpatient rehabilitation facility (IRF). Comorbidity indexes included tier comorbidity, Functional Comorbidity Index (FCI), Charlson Comorbidity Index, Elixhauser Comorbidity Index, and Hierarchical Condition Category (HCC). DESIGN: This was a retrospective cohort study. METHODS: Medicare beneficiaries with stroke, lower extremity joint replacement, and lower extremity fracture discharged to an IRF in 2011 were studied (N=105,441). Data from the beneficiary summary file, Medicare Provider Analysis and Review (MedPAR) file, and Inpatient Rehabilitation Facility-Patient Assessment Instrument (IRF-PAI) file were linked. Inpatient rehabilitation facility admission functional status was used as a proxy for acute hospital discharge functional status. Separate linear regression models for each impairment group were developed to assess the relationships between the comorbidity indexes and functional status. Base models included age, sex, race/ethnicity, disability, dual eligibility, and length of stay. Subsequent models included individual comorbidity indexes. Values of variance explained (R(2)) with each comorbidity index were compared. RESULTS: Base models explained 7.7% of the variance in motor function ratings for stroke, 3.8% for joint replacement, and 7.3% for fracture. The R(2) increased marginally when comorbidity indexes were added to base models for stroke, joint replacement, and fracture: Charlson Comorbidity Index (0.4%, 0.5%, 0.3%), tier comorbidity (0.2%, 0.6%, 0.5%), FCI (0.4%, 1.2%, 1.6%), Elixhauser Comorbidity Index (1.2%, 1.9%, 3.5%), and HCC (2.2%, 2.1%, 2.8%). LIMITATION: Patients from 3 impairment categories were included in the sample. CONCLUSIONS: The 5 comorbidity indexes contributed little to predicting functional status. The indexes examined were not useful as proxies for functional status in the acute settings studied.
Authors: K J Ottenbacher; J E Graham; A J Ottenbacher; J Lee; S Al Snih; A Karmarkar; T Reistetter; G V Ostir Journal: J Gerontol A Biol Sci Med Sci Date: 2012-03-02 Impact factor: 6.053
Authors: Gregory C Pope; John Kautter; Randall P Ellis; Arlene S Ash; John Z Ayanian; Lisa I Lezzoni; Melvin J Ingber; Jesse M Levy; John Robst Journal: Health Care Financ Rev Date: 2004
Authors: Dae Hyun Kim; Robert J Glynn; Jerry Avorn; Lewis A Lipsitz; Kenneth Rockwood; Ajinkya Pawar; Sebastian Schneeweiss Journal: J Gerontol A Biol Sci Med Sci Date: 2019-07-12 Impact factor: 6.053
Authors: Amit Kumar; Amol M Karmarkar; James E Graham; Linda Resnik; Alai Tan; Anne Deutsch; Kenneth J Ottenbacher Journal: J Gerontol A Biol Sci Med Sci Date: 2016-08-04 Impact factor: 6.053
Authors: Amit Kumar; Amol Karmarkar; Brian Downer; Amit Vashist; Deepak Adhikari; Soham Al Snih; Kenneth Ottenbacher Journal: Arthritis Care Res (Hoboken) Date: 2017-10-09 Impact factor: 4.794
Authors: Jason R Falvey; Allison M Gustavson; Lisa Price; Lucine Papazian; Jennifer E Stevens-Lapsley Journal: J Geriatr Phys Ther Date: 2019 Apr/Jun Impact factor: 3.381
Authors: Amit Kumar; James E Graham; Linda Resnik; Amol M Karmarkar; Alai Tan; Anne Deutsch; Kenneth J Ottenbacher Journal: Am J Phys Med Rehabil Date: 2016-12 Impact factor: 2.159
Authors: Amit Kumar; Linda Resnik; Amol Karmarkar; Janet Freburger; Deepak Adhikari; Vincent Mor; Pedro Gozalo Journal: Arch Phys Med Rehabil Date: 2019-01-24 Impact factor: 3.966
Authors: Michelle Vu; Florentina E Sileanu; Sherrie L Aspinall; Joshua D Niznik; Sydney P Springer; Maria K Mor; Xinhua Zhao; Mary Ersek; Joseph T Hanlon; Walid F Gellad; Loren J Schleiden; Joshua M Thorpe; Carolyn T Thorpe Journal: J Am Med Dir Assoc Date: 2020-07-25 Impact factor: 4.669