MEASUREMENT OF BODY COMPOSITION IN CHILDREN WITH PRADERLABHART-WILLI SYNDROME (PWS)

Abstract

We are currently investigating the effect of biosynthetic growth hormone (rhGH one year duration) on body composition, resting energy expenditure (REE) and total daily energy expenditure in 12 PWS children. We report here the measurements made before and after 6 weeks of rhGH therapy on 7 children (4F; age range 5.1-16.7 yr.; BMI 13.8-43.4). Total body water (TBW) was measured by H2 18O dilution, and calculated from measurements of skin fold thickness (SKF) and bioelectrical impedance analysis (BIA). These results were compared to those made in children with short stature. The different techniques were compared statistically by comparing the difference between the methods against their means.[l]. There was a significant correlation between total body water (TBW) measured by H2 18O dilution and the methods of BIA and SKF. However, the limits of agreement were greater than those seen in children with short stature (SS):Body composition calculated from BIA and SKF measurements are likely to be erroneous in very obese children. This should be taken into consideration if longitudinal changes of body composition are being monitored.[1] Bland IM Altman DG Statistical methods for assessing agreement between two methods; of clinical measurement Lancel 1986:1:307-310