THE EFFECT OF SIX WEEKS GROWTH HORMONE TREATMENT ON BODY COMPOSITION AND RESTING ENERGY EXPENDITURE IN PRADER-LABHART-WILLI SYNDROME (PWS)

Abstract

Growth hormone deficiency (GHD) is suggested as part of the hypothalamic disorder considered to be the basis for PWS - short stature, gross obesity, hypotonia. We are measuring the effect of treatment with 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 changes observed at 6 weeks on 7 children (4F; age range 5.1-16.7 yr.; BMI 13.8-43.4) compared with children treated with rhGH for GHD. Fat free mass (FFM, kg) and fat mass (FM, kg) were obtained from H2 18O dilution, REE (kj/24hr) was measured by indirect calorimetry. All results are expressed as mean(SE) and variance analysed by Wilcoxon rank test. All subjects gained weight. However, all 7 subjects significantly increased their FFM and in 6 there was a decrease in FM.: (* p<0.05)The mean change in FFM in PWS was significantly greater than in GHD subjects (14.4 v. 6.9%., p<0.01) One subject (14.2 yr., weight 78.2kg, BMI 33.9) developed diabetes mellitus after 3 wks of therapy (pre-treatment glycosylated haemoglobin 7.2%). Following 6 weeks of rhGH treatment, PWS children show a greater change in FFM than children with short stature. Growth hormone therapy may be appropriate for long term use in PWS as a means of increasing FFM with possible beneficial sequelae. However, it should be recognised that there is some risk of diabetes occurring.