Changes in Energy Expenditure, Physical Activity, and Hemoglobin Measures Associated with Fatigue Reports During Radiation Treatment for Breast Cancer: A Descriptive and Correlation Study

Abstract

Introduction: Radiation related fatigue is assessed through subjective evaluations that may not adequately describe the fatigue experience. This study measured changes in energy expenditure (Kcals/day), steps per day (SPD), and hemoglobin (Hb) in women undergoing radiation for breast cancer and evaluated correlations with fatigue reports. Subjects: 17 females [51.2 (10.3) years of age] scheduled to receive radiation for breast cancer. Methods/Materials: A prospective, repeated measures design measured Kcals/day and SPD during the first, fourth, and sixth weeks of radiation using the SenseWear© Body Monitoring System. Fatigue reports were assessed weekly using the Brief Fatigue Inventory (BFI), and Hb was measured the first and sixth weeks of treatment. Friedman's Analysis of Variance assessed differences over time and Pearson's Product Moment determined correlations between variables with p ≤ .05 considered significant. Results: Energy expenditure was similar between weeks one [2164 (317) Kcals/day] and 4 [2198 (424) Kcals/day] but declined significantly (p = .012) at week 6 [2103 (390) Kcals/day] by 4.3%. Steps per day were similar between weeks one [7382 (3768)] and 4 [7407 (5079)], but declined significantly (p = .014) by 14.02% by week 6 [6369 (4156)]. The BFI scores gradually increased by 43.31%; changes were not statistically significant (p = .145). Correlations were significant between Kcals/day and BFI (r = -.346, p = .011), between Hb and Kcals/day (r = .458; p = .003), and between Hb and SPD (r = .426; p = .006). Conclusions: The study found an inverse correlation between energy expenditure and fatigue scores and a positive correlation between Hb and Kcals/day as well as SPD. Women with the highest fatigue scores had the lowest Kcals/day, SPD, and Hb; therefore, maintaining healthy activity levels and monitoring Hb may reduce fatigue reports and preserve function during radiation for breast cancer.