SP372ESTIMATION OF BODY COMPOSITION IN HEMODIALYSIS PATIENTS USING THREE BIOIMPEDANCE DEVICES

Abstract

INTRODUCTION AND AIMS: Accurate and precise assessment of body composition (BC) including total body water (TBW), fat mass (FM), skeletal muscle mass (SMM) and lean body mass (LBM) is crucial to evaluate nutritional status in hemodialysis (HD) patients. Several studies have shown independent association with specific BC markers and survival time. The assessment of BC using bioimpedance spectroscopy has proven to be a valid method among healthy and HD populations. The aim of this study was to compare three commercially available bioimpedance devices with respect to measurements of peridialytic BC changes in HD patients, and to compare the results of healthy subjects (HS). METHODS: Ten HD patients (8 males, age 61.9±12 years) and 12 HS (5 males, 33.365.6 years) were studied. Measurements were performed before and after HD treatment in patients and once in HS. We used three multi-frequency bioimpedance devices: InBody 770 (InBody USA, Cerritos, CA), Seca mBCA 514 (Seca North America, Chino, CA), and Hydra 4200 (Xitron Technologies, San Diego, CA) with standing position for all devices. InBody and Seca report TBW, FM, LBM, and SMM. Hydra provides extracellular (ECV), intracellular (ICV) volume and body mass (BM) and TBW. FM, LBM, and SMM were calculated using the body composition model by Chamney (Am J Clin Nutr, 2007). We analyzed peridialytic BC changes and BC in HS. RESULTS: BM were 73.7 kg, 75.05 kg and 72.42 kg for HS, and for patients before and after HD treatment, respectively. All three devices reported a significant peridialytic decrease in TBW for HD patients (Fig. a). LBM decreased in InBody and Seca results, but not significantly in Hydra (Fig. b). FM decreased in Hydra but did not change much in InBody and increased in Seca (high variability) (Fig. c).SMM had no change in Seca and Hydra, while a significant decrease was reported by InBody (Fig. d). The pre-HD FM-to-BMratio (%FM) was higher in Hydra compared to InBody and Seca, respectively. In HS, however, %FM was significantly higher in Seca compared to Hydra and InBody, respectively. LBM and SMM were lower in both HD and HS with Hydra compared to InBody and Seca, respectively (Table 1). CONCLUSIONS: The disagreements in measurement of body composition with different bioimpedance devices may be attributed to the differences in the mathematical body composition models used by these three devices. This may imply that the accuracy of measurement needs to be improved for clinical application, especially for HD population (Table presented).