Growth hormone and body composition in children younger than 2 years with Prader-Willi syndrome

Objectives To assess body composition of infants with Prader-Willi syndrome (PWS) by using deuterium dilution and investigating the efficacy of early institution of growth hormone (GH) therapy in increasing lean mass (LM) and preventing massive obesity. Study design One group of 11 children with PWS <2 years before and during 30-month GH therapy (GH group) was compared with 6 infants administered only coenzyme Q(10) for 1 year (Q10 group). LM adjusted for height (LMHt) and relative fat mass (%FMAge) standard deviation scores (SDS) were calculated from data of 95 healthy children. Results Initially, LMHt of all patients was below the normal average. LMHt decreased by -0.46 +/- 0.3 SD (P = .03) per year in the Q10 group but rose by 0.25 +/- 0.3 SD (P = .02) per year during GH therapy, normalizing after 30 months (-0.70 +/- 1.0 SD). Despite low to normal weight for height (WfH), %FMAge was above the normal average (GH group, 31.0% +/- 4.5%, Q10 group, 32.4% +/- 9.5%). In the Q10 infants, %FMAge increased by 0.71 +/- 0.7 SD per year, whereas in the GH group, %FMAge remained more stable up to 30 months. Conclusions Diminished LMHt found in infants with PWS further declines during the early years. Early institution of GH therapy lifts LMHt into the normal range and delays fat tissue accumulation.