Factors correlated with fatigue in terminally ill cancer patients: a longitudinal study

Fatigue is among the most distressing symptoms experienced by terminally ill cancer patients. It is necessary to clarify factors correlated with fatigue to develop effective management strategies. A consecutive sample of cancer patients newly registered in the Palliative Care Unit (PCU) was assessed on three occasions: at the second visit to the outpatient clinic of the PCU (Time 1), three weeks after the Time 1 session over the telephone (Time 2), and at admission to the PCU (Time 3). The patients' fatigue and a broad range of biopsychosocial factors were assessed using the validated questionnaires, structured interviews, and medical record reviews at Time 1 and Time 3. Fatigue was the only factor assessed at Time 2. Two hundred patients participated in the Time 1 session, and 129 and 73 were followed at Time 2 and Time 3, respectively. Greater fatigue at Time 1 was significantly correlated with psychological distress, lower Karnofsky Performance Status score, dyspnea, and appetite loss (adjusted coefficients of determination [R(2)]=0.49). Greater fatigue at Time 2 was significantly correlated with psychological distress, lower Karnofsky Performance Status and fatigue at Time 1 (adjusted R(2)=0.51). Greater fatigue at Time 3 was significantly correlated with changes for the worse in psychological distress, Karnofsky Performance Status, and dyspnea severity during the period between Time 1 and Time 3, after adjusting for Time 1 fatigue (adjusted R(2)=0.54). The results indicate that fatigue in terminally ill cancer patients is determined by both physical and psychological factors. It may be important to include psychological intervention in the multidimensional management of fatigue in this population, in addition to physical and nursing interventions.