Background: Cancer patients with chemotherapy-induced anaemia (CIA) often experience cancer-related fatigue (CRF). Darbepoetin alfa (DA) once every 3 weeks (q3w) is an effective and well tolerated erythropoiesis-stimulating agent. This study evaluated DA effectiveness and psychometric properties of the Functional Assessment of Cancer Therapy Fatigue-Subscale (FACT-F) and the Fatigue Symptom Inventory (FSI) in CIA patients.
Methods: This was a single-centre, prospective study in 100 patients with solid tumour and moderate to severe CRF (visual analogue scale [VAS-F] ≥ 30 mm) who received DA 500 μg q3w during chemotherapy (CT). Clinical data, VAS-F, FACT-F and FSI scores were collected at the beginning and at the end of CT (EOCT).
Results: Mean age was 62.7 years (SD: 12.1), 53.0% were women, 92.0% had ECOG 0-1 and 64% had stage IV tumours. Mean haemoglobin (Hb) significantly increased from baseline 10.2 g/dl to 11.3 g/dl at EOCT. Sixty-five percent of patients showed haematopoietic response at any study point (Hb ≥ 12 g/dl or an increase of ≥ 2 g/dl from baseline), 77% achieved Hb ≥ 11 g/dl and 7% required blood transfusions from week 5 to EOCT. CRF improvement was demonstrated by significant changes in VAS-F, FACT-F and FSI scores (decreases of 21.54, 3.56 and 12.97 points, respectively). FACT-F and FSI questionnaires showed high internal consistency (Cronbach's alpha of 0.98 and 0.98 for FACT-F and FSI, respectively, at the end of study) and satisfactory intra-class coefficients (FACT-F, r=0.73; FSI, r=0.83). There were significant correlations between scores and Hb changes (FACT-F, r=-0.44; FSI, r=-0.54).
Conclusions: DA 500 μg q3w showed effectiveness in improving Hb and inducing a clinically significant decrease in CRF of patients with solid tumours undergoing CT. The three instruments, VAS-F, FACT-F and FSI, could be suitable for assessing CRF.