부산대학교 도서관

BACKGROUND: The body composition in overweight and obese hemodialyzed patients (HD) remains ill-defined. This study evaluates in HD patients the influence of body size, as indicated by body mass index (BMI, kg/m²), on body composition by measuring bioimpedance analysis (BIA)-derived variables (phase angle (PA), fat-free mass (FFM) and body cell mass (BCM). METHODS: We studied 50 Caucasian patients (mean age 62.8±9.2 y) on standard bicarbonate hemodialysis for at least 12 months who regularly achieved dry weight in post-HD, received similar dialysis doses and were free from inflammation/infection. Thirty-eight gender- and age-matched healthy subjects were included as controls (CON). Both HD and CON were divided into three groups on the basis of their BMl(kg/m²) 18.5-24.9, normal-weight (NW); 25-29.9, overweight (OW); and ≥30, obese (OB). In HD patients, BIA was performed 30 min after the end of dialysis. RESULTS: Seven patients were obese (12%) while 16 were overweight (32%); in CON, 12 were obese (31%) and 12 overweight (31%). BIA-measured extracellular water was comparable in all groups. PA, which was similar in normal-weight HD and CON (6.2±0.9° and 6.3±0.8°), decreased in OW- and OB-HD patients (5.3±1.0° and 5.2±0.6°, respectively; P < 0.05 vs NW-HD) while it was unchanged in OW- and OB-CON (6.1±0.8° and 5.9±0.5°, P<0.05 vs respective HD groups). In OW and OB patients, the lower PA values were coupled with a major reduction of BIA-derived percentage BCM and FFM (P<0.05 vs NWHD, and vs OW- and OB-CON). In patients, PA and BCM correlated with anthropometry-measured FFM. Of note, serum albumin and protein catabolic rate were significantly reduced in OB patients. CONCLUSION: In overweight and obese HD patients, BIA-derived FFM, BCM and PA are significantly lower with respect to normal-weight patients and BMI-matched controls. These abnormalities of body composition are coupled... [ABSTRACT FROM AUTHOR]