Clinical Significance of Volume Status in Body Composition and Physical Performance Measurements in Hemodialysis Patients

INTRODUCTION: This study aimed to evaluate the association between volume status and body composition or physical performance measurements in hemodialysis patients. METHODS: A total of 84 patients were enrolled in this study. The participants were divided into tertiles based on the edema index (extracellular water/total body water): low, middle, and high tertiles. Serum albumin and serum high-sensitivity C-reactive protein levels were measured. The appendicular lean mass index (ALM/Ht(2), kg/m(2)) was measured using dual-energy X-ray absorptiometry. The thigh muscle area index (TMA/Ht(2), cm(2)/m(2)) was measured using CT. Extracellular and total body water and phase angles were obtained using bioimpedance analysis. The results of the subjective global assessment (SGA), hand-grip strength (HGS), gait speed (GS), short physical performance battery (SPPB), sit-to-stand for 30-second (STS30) test, timed up and go (TUG), sit-to-stand test performed five times (STS5), and 6-minute walk (6-MW) tests were also evaluated. RESULTS: On the univariate analysis, the SGA score and phase angle in the high tertile group were the lowest among the three groups. On multivariate analysis, TMA/Ht(2) and phase angle in the high tertile were the lowest among the three groups. Inverse correlations were observed between edema index and TMA/Ht(2), SGA score, phase angle, HGS, GS, SPPB, STS30, or 6-MW. Positive correlations were observed between the edema index and the STS5 or TUG test. The sensitivity and specificity for predicting low GS were 34.5 and 89.7%, respectively. The values for predicting low SPPB were 68.0 and 79.7%, respectively. CONCLUSION: This study demonstrates that high volume status may be associated with decreased muscle mass and physical performance regardless of inflammatory or nutritional status.