Medical comorbidity and rehabilitation efficiency in geriatric inpatients

OBJECTIVES: To measure and describe medical comorbidity in geriatric rehabilitation patients and investigate its relationship to rehabilitation efficiency. DESIGN: Prospective, multivariate, within-subject design. SETTING: The Geriatric Rehabilitation inpatient unit of the SCO Health Service in Ottawa, Canada. PARTICIPANTS: One hundred ten patients, with a mean age of 82 years. MEASUREMENTS: The rehabilitation efficiency ratio, based on gains in functional status achieved with rehabilitation treatment, and the length of stay were computed for all patients. Values were regressed on the scores of the Cumulative Illness Rating Scale (CIRS), the Mini-Mental State Examination, and the Geriatric Depression Scale to establish predictive power. RESULTS: The findings suggest that geriatric rehabilitation patients experience considerable medical comorbidity. Sixty percent of patients had impairments across six of the 13 dimensions of the CIRS, whereas 36% of patients had impairments across 11 of the 13 dimensions. In addition, medical comorbidity was negatively related to rehabilitation efficiency. This relationship was significant even after controlling for age, cognitive status, depressive symptoms, and functional independence status at admission. CONCLUSION: Medical comorbidity was a significant predictor of rehabilitation efficiency in geriatric patients. Comorbidity scores >5 were prognostic of poorer rehabilitation outcomes and can serve as an empirical guide in estimating a patient's suitability for rehabilitation. Medical comorbidity predicted both the overall functional change achieved with rehabilitation (Functional Independence Measure gains) and the rate at with which those gains were reached (rehabilitation efficiency ratio).