Cancer-related fatigue: predictors and effects of rehabilitation

BACKGROUND: The aims of the study were to examine the effects of a multidimensional rehabilitation program on cancer-related fatigue, to examine concurrent predictors of fatigue, and to investigate whether change in fatigue over time was associated with change in predictors. METHODS: SAMPLE: 72 cancer survivors with different diagnoses. SETTING: rehabilitation center. INTERVENTION: 15-week rehabilitation program. MEASURES: Fatigue (Multidimensional Fatigue Inventory), demographic and disease/treatment-related variables, body composition (bioelectrical impedance), exercise capacity (symptom-limited bicycle ergometry), muscle force (handheld dynamometry), physical and psychological symptom distress (Rotterdam Symptom Check List), experienced physical and psychological functioning (RAND-36), and self-efficacy (General-Self-Efficacy Scale, Dutch version). Measurements were performed before (T0) and after rehabilitation (T1). RESULTS: At T1 (n = 56), significant improvements in fatigue were found, with effect sizes varying from -0.35 to -0.78. At T0, the different dimensions of fatigue were predicted by different physical and psychological variables. Explained variance of change in fatigue varied from 42%-58% and was associated with pre-existing fatigue and with change in physical functioning, role functioning due to physical problems, psychological functioning, and physical symptoms distress. CONCLUSIONS: Within this selected group of patients we found that (a) rehabilitation is effective in reducing fatigue, (b) both physical and psychological parameters predicted different dimensions of fatigue at baseline, and (c) change in fatigue was mainly associated with change in physical parameters