Differences in fatigue experiences among patients with advanced cancer, cancer survivors, and the general population

Fatigue is a multidimensional symptom experienced physically, cognitively, and emotionally. Research on fatigue experiences in various stages of cancer might help to elucidate the nature of cancer-related fatigue.

To compare fatigue experiences in advanced cancer patients (ACPs), cancer survivors (CSs), and controls from the general population (GenPop).

Sixty-three ACPs (no antitumor therapy in the last month and no options for future therapy) were matched for age, sex and diagnosis with 63 CSs (last treatment one to five years ago) and 315 controls. Fatigue was measured unidimensionally with the Numeric Rating Scale and multidimensionally with the Multidimensional Fatigue Inventory.

All fatigue levels (general fatigue, physical fatigue, reduced activity, reduced motivation, and mental fatigue) were higher in ACPs than in CSs and controls (P<0.01), whereas fatigue levels were not different between CSs and controls. NRS scores in ACPs and CSs were significantly predicted by the fatigue dimensions physical fatigue and mental fatigue only. Although physical fatigue and mental fatigue were strongly related in the GenPop, the relation was weaker in CSs and not significant in ACPs. In multivariate analyses, only physical fatigue differentiated ACPs from CSs and controls (P<0.01).

ACPs experience fatigue more intensely than CSs and controls when fatigue is measured multidimensionally. Although mental and physical dimensions of fatigue contribute to the overall experience of fatigue in both groups of cancer patients, physical fatigue best differentiated ACPs from both CSs and controls.