Medical Comorbidity and Complexity of the Rehabilitative Procedures for Older Patients with Functional Impairments

To the Editor: In their article recently published in the Journal of American Geriatrics Society,1 Patrick et al. observed that medical comorbidity is a significant predictor of rehabilitation efficiency in geriatric inpatients. We want to contribute to this topic by stating that the intensity and the complexity of rehabilitative procedures, which are different for various levels of comorbidity, mediate this correlation. For this purpose, we retrospectively reviewed the clinical data and the rehabilitative procedures of 80 older patients consecutively admitted to our 20-bed rehabilitation unit from July to October 2001. Thirty-seven subjects had orthopedic injuries, 17 gait disorders related to cerebrovascular disease, 13 hemiparesis from a recent stroke, 11 gait disorders related to arthritis, and two peripheral vascular diseases. The rehabilitative procedures were analyzed with an index (Rehabilitative Procedure Index, RPI) created to evaluate the level of intensity and complexity of rehabilitative procedures in the hospital. Previously, a chart list was defined, including all the rehabilitative procedures adopted during the rehabilitation of geriatric inpatients. The list graded three levels of complexity for each rehabilitative procedure (low, medium, and high), based on the degree of coordination and the emotional participation requested of the patient. The total number of the rehabilitative procedures performed by the single patient during the hospital stay was recorded. The index was obtained by multiplying the total number of rehabilitative procedures by complexity level and dividing the result by the length of hospital stay (days). Table 1 shows the characteristics of the patients stratified in four groups, according to the comorbidity level (first group, Charlson Index = 0–3; second group, Charlson Index ≥4) and the Tinetti score2 on admission (first subgroup, Tinetti = 0–12; second subgroup, Tinetti = 13–28; cutoff at 50th percentile). We found that the change in functional performances from admission to discharge (delta Tinetti), the total number of rehabilitative procedures, and the RPI (the intensity and the complexity of rehabilitative procedures) were significantly different in the four groups. Furthermore, the interactive effect of Tinetti and comorbidity (analysis of variance) was greater in subjects with low comorbidity and smaller in subjects with high comorbidity, suggesting that comorbidity represents a barrier to intensive rehabilitative programs. These data also suggest that the effect of comorbidity on the functional outcomes is not direct but is mediated by the different levels of complexity and intensity of the rehabilitative procedures. Comorbidity influences the physical therapists in determining a patient's ability to sustain rehabilitative training of various intensity and complexity levels. It would be of extreme importance to individualize the different rehabilitative procedures, allowing better functional outcomes under the same clinical conditions, and to standardize the selection criteria of patients for the different levels of the rehabilitative programs.