Assessing energy expenditure in cancer patients: A pilot validation of a new wearable device

Background: Nutrition problems are common in cancer patients and are frequently due to metabolic derangements. Thus, accurately assessing energy expenditure (EE) is important in planning adequate nutrition support. Indirect calorimetry (IC) represents the gold standard method but is not always available or applicable to all settings. The purpose of this study was to preliminary compare a new wearable device, the SenseWear armband (SWA), to IC in cancer patients. Methods: Ten (6 M, 4 F) subjects (mean +/- SD: 56.6 +/- 13.3 years) affected by newly diagnosed acute myelogenous leukemia, undergoing induction chemotherapy, were prospectively enrolled. Resting EE (REE) was measured simultaneously by SWA and IC on admission (day 0) and at discharge (end). Total daily EE (TDEE) was determined by SWA 4 times during the stay (days 0, 7, 14, and end) and predicted values were calculated according to IC, REE estimates (TDEE = IC X correction factor 1.2). Results: Mean length of stay was 27.1 +/- 6.2 days. Bland-Altman plots revealed no significant differences between overall REE estimates (day 0 + end) performed by IC and SWA (mean +/- SD; 1645 +/- 282 vs 1705 +/- 278 kcal/d) and the correlation was high (r = 0.84; P <.0001). SWA TDEE showed a progressive reduction during the stay. No bias was detected between overall SWA TDEE (1799 +/- 153 kcal/d) and IC predicted TDEE (1974 +/- 176 kcal/d), but there was a wide 95% confidence interval (-672; +321 kcal/d). Moreover, the correlation between these values was significant (r = 0.68; p =.001). Conclusions: SWA seems to provide accurate and reliable estimation of REE and useful information on TDEE also in cancer patients. Its use appears promising. Validation studies on larger samples and different cancer types should be considered.