BODY-COMPOSITION BY BIOELECTRICAL-IMPEDANCE ANALYSIS COMPARED WITH DEUTERIUM DILUTION AND SKINFOLD ANTHROPOMETRY IN PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY-DISEASE

Body composition is an important measure of nutritional status in patients with chronic obstructive pulmonary disease (COPD). We generated a regression model for bioelectrical impedance (BI) by using deuterium dilution ((H2O)-H-2) as a reference method in 32 COPD patients, aged 63 +/- 9 y (xBAR+/-SD), in stable pulmonary and cardiac condition. Height squared divided by resistance (Ht2/Res) correlated well with total body water (TBW) as measured by (H2O)-H-2 (r = 0.93, P < 0.001, SEE = 1.9 L). The best-fitting regression equation to predict TBW comprised Ht2/Res and body weight (r2 = 0.89, SEE = 1.8 L, P < 0.001). BI-predicted TBW was used to estimate BI-fat-free mass (FFM) that was compared with skinfold-thickness-based FFM predictions (Anthr-FFM). Relative to BI-FFM a significant overestimation of 4.4 +/- 0.8 kg was found by Anthr-FFM. Our results suggest that BI is a useful measure of body composition in patients with severe COPD.