[Estimation of body composition in patients on dialysis by means of near-infrared interaction ].

Malnutrition and low serum albumin values predict increased mortality in uremic patients. Infrared interactance represents a novel approach to the estimation of body composition. We have examined total body fat, body water and fat-free weight in our male haemodialysis (n = 24) and peritoneal dialysis (n = 17) patients. There were no differences between the groups in a cross-sectional study. A longitudinal study showed a significant increase of total body fat (%) in the peritoneal dialysis patients after five months (mean values +/- SEM) (from 19.8 +/- 2.3 to 22.6 +/- 2.4, p < 0.05), and a significant decrease of body water (%) (from 59.9 +/- 1.5 to 58.2 +/- 1.6, p < 0.05). The difference in total body fat between the haemodialysis (n = 14) and peritoneal dialysis (n = 10) groups reached statistical significance (16.5 +/- 1.7 versus 22.6 +/- 2.4, p < 0.05). No difference was found in serum albumin. Infrared interactance has the capacity to characterize time-dependent differential changes of body composition in various dialysis modalities. Further studies are needed to describe the validity of the method for identification of patients with increasing malnutrition.