PROLONGED EXPERIENCE WITH A LONG-ACTING G ONADOTROPIN-RELEASING-HORMONE ANALOG IN THE TREATMENT OF CENTRAL PRECOCIOUS PUBERTY - EFFECT ON GROWTH

In central precocious puberty (CPP), characterised by premature but ot herwise normal puberty, the early onset of the pubertal growth spurt w ith increased height velocity results in premature epiphyseal closure with reduced final height. We examined the growth pattern in 11 patien ts (9 girls and 2 boys) with CPP treated with a long-acting gonadotrop in-releasing hormone analogue (GNRHa). Every 28 days 75 mu g of the GN RHa Triptorelin (Decapeptyl CR(R), Fa. Ferring) per kg body weight are given intramuscularly. We observed body height, height velocity, bone maturation (dBA/dCA) and predicted adult height in these patients for up to 4 years. Before treatment body height was markedly elevated (2. 5 +/- 4.4 SD above the age appropriate mean); after two years on thera py it reached the normal range. Height velocity decreased significantl y within the first six months of treatment and remained subsequently l ow (F = 7.59; p<0.0001). In the first year on treatment bone maturatio n (dBA/dCA) dropped from 1.8 +/- 0.42 to 0.7 +/- 0.27 and in the secon d year to its lowest value of 0.3 +/- 0.13 (F = 2.35; p<0.05). The pre dicted adult height increased from 154.5 +/- 4.0 cm at the beginning o f treatment to 160.3 +/- 3.9 cm at the most recent follow-up examinati on. The present data indicate that treatment with a long-acting GNRHa markedly affects body growth in CPP by reducing height velocity and de laying bone maturation. The predicted adult height appears to increase , consequently.