ABSTRACT
BACKGROUND: Asthenia fatigue syndrome (AFS) is a common symptom perceived by patients with cancer and consists of reported pathologic fatigue, poor endurance, and impaired motor and cognitive function. OBJECTIVE: The purpose of this study was to examine the relationship between a traditional measure of AFS, visual analogue scale (VAS) fatigue ratings, and a set of more objective functional and physiologic measures (Dietz oncology classification, C-reactive protein, serum albumin, hemoglobin, body mass index [BMI]), Motor Functional Independence Measure (FIM) Score, Cognitive FIM Score. We hypothesized a relationship could suggest the utility of alternative means of assessing and addressing AFS. METHODS: We retrospectively examined the records of 131 patients admitted to our facility for inpatient rehabilitation because of disability-causing cancer or its treatment. RESULTS: Of our sample, 94.7% (124 cases) indicated at least mild fatigue and 97.7% (128 cases) showed abnormal serum albumin, C-reactive protein, hemoglobin, or BMI. We used multiple regression analysis to examine the relationship between VAS fatigue ratings and the aforementioned set of functional and physiologic variables. The regression explained a significant proportion of the variability in VAS fatigue ratings (F = 2.25, df = 7,123, p = 0.03, R = 0.34, R(2) = 0.11). However, only Motor FIM Score accounted for a significant independent contribution to the variability in VAS fatigue ratings. CONCLUSION: The data indicate physiologic and functional variables may provide an alternative, objective, and reliable operational definition of AFS. Specifically, using Motor FIM Score, as a surrogate for VAS fatigue ratings may be used to measure the efficacy of AFS treatment.