Cocalibrated Functional Score and Subsequent Post-Acute-Care (PAC) Utilization

PURPOSE: Maintaining functional ability can optimize independence and quality of life for hospitalized older adults [1-3]. However, current knowledge of functional status, PAC utilization and quality measures (e.g. hospital readmission) remains sparse. The Improving Medicare Post-Acute Care Transformation Act (IMPACT Act) of 2014 mandated hospitals and post-acute care (PAC) providers to report quality measures to consumers across care continuum. Thus, it is crucial to connect the gap between what the therapists’ interest (e.g. function) and what health policy makers’ interest (e.g. hospital readmission). This study aims to examine the roles of two functional domains (self-care and mobility) in determining subsequent PAC utilization. The finding of this study provides insights for the occupational therapists to facilitate the optimal care quality across care continuum, by understanding the associations between patients’ functional status and the subsequent PAC utilization.

DESIGN: We conducted secondary data analysis of 100% 2013-2014 Medicare claims data, covering 540,526 cases with three impairment conditions: stroke, lower extremity joint replacement (LEJR) and hip/femur fracture (HFF). Admission functional scores were separated by two domains (self-care and mobility) and co-calibrated into a 0-100 scale for three functional assessments: (a) Inpatient Rehabilitation Facility Patient Assessment Instrument, used in inpatient rehabilitation facility (IRF); (b) Minimum Data Set, used in skilled nursing facility (SNF); and (c) Home Health Outcome and Assessment Information Set, used in home healthcare (HH).

METHODS: We linked Medicare Provider Analysis and Review file with the provider of service file. Generalized linear mixed model was developed to estimate proportion of variations of the subsequent PAC utilization based on the co-calibrated admission functional scores. All models were ran separately by impairment conditions. The included covariates were at: (1) patient-level (age, gender, race/ethnicity, original entitlement, type of impairment, Elixhauser comorbidities, length of stay and dual eligibility) and (2) facility-level (profit status, teaching status, hospital size, types of facility [rehab unit in hospital/free standing], disproportionate share, specialized hospital and critical access hospital).

RESULTS: Overall, among those who used 1st PAC (n=540,526), 41.9% used 2nd PAC (n=226,364); and among those who used 2nd PAC, 8.6% used 3rd PAC (n=18,378). Beneficiaries at HH had overall higher functional scores, except in one condition (mobility for LEJR). Less than 5% of the beneficiaries in HH continued to use the second PAC, implying HH could be considered as the last service utilization location. For stroke, co-calibrated functional scores (self-care and mobility) explained 13.9% variance of subsequent PAC utilization for IRF, and 0.8% for SNF. For LEJR, co-calibrated functional scores explained 3.2% variance of subsequent PAC utilization for IRF, and 0.8% for SNF. For HFF, co-calibrated functional scores explained 5.9% variance of subsequent PAC utilization for IRF, and 0.1% for SNF.

CONCLUSION: Variations in post-acute utilization were attributable to co-calibrated admission functional score, and such variations differed by impairment conditions and settings. Overall, functional scores at IRFs explained larger variances of PAC utilization than those explained by SNFs. Patient-level functional status could be one of the driving forces for the patients to select one type of post-acute setting over other. Future work should take into account this patient-level ‘selection bias’ associated with PAC utilization, especially when comparing health quality outcomes across PAC settings.

References

1. Paterson, D. H., & Warburton, D. E. (2010). Physical activity and functional limitations in older adults: a systematic review related to Canada's Physical Activity Guidelines. Int J Behav Nutr Phys Act, 7:38. doi:10.1186/1479-5868-7-38.

2. Covinsky, K. E., Palmer, R. M., Fortinsky, R. H., Counsell, S. R., Stewart, A. L., Kresevic, D., Burant, C. J., & Landefeld, C. S. (2003). Loss of independence in activities of daily living in older adults hospitalized with medical illnesses: increased vulnerability with age. J Am Geriatr Soc, 51(4), 451-8.

3. Sager, M., Franke, T., Inouye, S., Landefeld, C., Morgan, T., & Rudberg, M. (1996). Functional outcomes of acute medical illness and hospitalisation in older persons. Arch Int Med. 156:645-8.