Could Objective Tests Be Used to Measure Fatigue in Patients With Advanced Cancer?

<bold>Context: </bold>Assessment of cancer-related fatigue is currently based on patient-reported outcomes. We asked whether objective assessments, such as muscle strength and nutritional markers, can be used as surrogate measures of cancer-related fatigue.<bold>Objective: </bold>We examined the association among three fatigue scales, muscle strength, and nutritional markers in patients with advanced cancer.<bold>Methods: </bold>In this prospective study, we enrolled hospitalized cancer patients who had been seen in palliative care consultation at MD Anderson Cancer Center. We assessed fatigue using three fatigue scales-the Brief Fatigue Inventory (BFI), the Edmonton Symptom Assessment System (ESAS), and the European Organization for Research and Treatment of Cancer Quality of Life Core Questionnaire 30 (EORTC QLQ-C30)-and determined their association with objective assessments, including handgrip strength, maximal inspiratory pressure, lean body mass, phase angle, and albumin. Spearman's correlation test was used to assess associations.<bold>Results: </bold>Among 222 patients, the mean age was 55 years; 59% were women. The median overall survival was 106 days. The total BFI score had weak association with handgrip strength (ρ = -0.18, P = 0.007) and no association with the remaining objective measures. ESAS fatigue and EORTC fatigue showed similar findings. Total BFI had moderate-to-strong association with ESAS (ρ = 0.54, P < 0.0001) and EORTC (ρ = 0.60, P < 0.0001) fatigue.<bold>Conclusion: </bold>Our study showed that subjective assessment of fatigue based on patient-reported outcomes correlates only weakly with muscle strength and nutritional markers; thus, patient-reported outcomes remain the gold standard for fatigue assessment. [ABSTRACT FROM AUTHOR]