UCSF

OBJECTIVE: To compare characteristics between middle-aged and older prosthesis users with and without cognitive impairment and determine whether cognitive impairment contributes to variability in perceived physical function. DESIGN: Cross-sectional, observational study SETTING: General community. PARTICIPANTS: Adults 45 years or older, at least 1-year post lower limb amputation (LLA) who were walking independently with a prosthesis (N=119). INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: We identified cognitive impairment using an education-adjusted Telephone Interview for Cognitive Status-modified score. Perceived physical function was measured using the Prosthesis Mobility Questionnaire. RESULTS: Of 119 participants (mean age, 62.6±8.2 years; male: 89.1%; vascular etiology: 82.4%; years since amputation: 4.9±4.7 years), 28 (23.5%) had cognitive impairment. Compared with participants without cognitive impairment, those with cognitive impairment were more likely to use an assistive device (60.7% vs 25.3%, P=.002); were older (66.3±7.3 vs 61.5±8.1 years, P=.006) and had more chronic conditions (7.1±3.4 vs 5.4±2.5, P=.004), more depressive symptoms (6.6±5.1 vs 4.2±3.8, P=.008), and worse perceived physical function (2.0±0.6 vs 2.6±0.7, P<.001). Using backward stepwise linear regression, we found that participants with cognitive impairment had worse perceived physical function (standardized parameter estimate [β]=-0.15, P=.02), even after adjusting for depressive symptoms (β=-0.31, P<.001), prosthesis satisfaction (β=0.34, P<.001), number of chronic conditions (β=-0.19, P=.006), and assistive device use (βcane=0.01, P=.93; βother=-0.20, P=.003). Together, these variables explained 59% of perceived physical function variability. CONCLUSIONS: Cognitive impairment is common and associated with worse perceived physical function post LLA, even after controlling for physical and mental health differences. Tailored rehabilitation interventions may be needed to improve perceived physical function in prosthesis users with cognitive impairment.