At least part of the short stature in Prader-Willi syndrome may be exp
lained by a decreased growth hormone (GH) secretory capacity, which oc
curs in most patients. To study the effects of exogenous GH on growth
and body composition, 17 prepubertal children with Prader-Willi syndro
me, with a short projected final height, were randomized to a control
group (n = 9) or a treatment group (n = 8). Children in the treatment
group received GH (0.15 IU/kg/day s.c.) for 1 year. One patient in the
treatment group developed pseudotumour cerebri, which resolved after
discontinuation of GH; this patient was omitted from further analysis.
After 1 year, height velocity in the GH-treated group was significant
ly increased (+5.5 SD) compared with reference values for normal healt
hy children, whereas there was a decrease in the control group (-2.3 S
D). The difference in height velocity between the treated and control
groups was significant (p = 0.0012). Concentrations of both insulin-li
ke growth factor I (IGF-I) and IGF-binding protein-3 increased signifi
cantly in the GH-treated group (p < 0.008). A gain in height was noted
for chronological age (+1.07 SD) after 1 year of GH treatment. Height
gain (+1.02 SD) remained unchanged when analysed in relation to bone
age. No differences between the groups were found for parameters of we
ight and body composition. In conclusion, although GH appears to have
beneficial effects on height, long-term studies are necessary before r
ecommendations can be made concerning GH treatment in children with Pr
ader-Willi syndrome.