Correlation between hemoglobin and fatigue in women undergoing adjuvant chemotherapy without erythropoietin-stimulating-agent support.

BACKGROUND: Fatigue is a common complication of adjuvant chemotherapy and compromises the quality of life of breast cancer survivors. We sought to correlate serial hemoglobin (Hb) levels with fatigue in a population of women on adjuvant chemotherapy, none of whom received erythropoietin-stimulating agents or red blood cell transfusions. PATIENTS AND METHODS: Seventy-five women participated in a study using quality-of-life questionnaires to assess changes in need for psychosocial support over time. Questionnaires were administered within 30 days of initiating adjuvant therapy and at 2, 6, and 12 months. Fatigue was assessed by the 36-Item Short-Form Health Survey (SF-36). Hemoglobin levels at each time point were captured retrospectively. Complete data are included for 40 of the 46 women who received adjuvant chemotherapy. Paired-samples t tests were conducted to compare mean SF-36 Energy/Fatigue scores between time points, and independent-samples t tests were conducted for comparisons against norms. Simple correlations (Pearson R) were conducted between SF-36 variables and Hb levels at each time point.
RESULTS: At 2 months, 23.4% of women had Hb<11 g/dL compared with 12.9% at 12 months. Compared with norms for women in the general population and breast cancer survivors, these women reported worse fatigue at baseline and at 2 and 6 months. A strong linear relationship was observed between Hb at 2 months and SF-36 Energy/Fatigue scores at 12 months (r=0.71; P=.002).
CONCLUSION: Participants with high fatigue at 12 months had Hb levels at 2 months 13% lower than those with low fatigue. This finding suggests that chemotherapy-induced decline in Hb might be a marker of physiologic reserve.