Effects of Treatment with Long-acting Gonadotropin-releasing Hormone Agonist on Somatic Growth in Patients with Central Precocious Puberty

Yoo, So Young; Yoo, Han Wook

Abstract

PURPOSE
Precocious puberty is the development of secondary sexual characteristics before the age of 8 years in girls and 9.5 years in boys. It is usually associated with premature, rapid skeletal maturation and closure of the epiphyseal plates, resulting in short stature compared with genetic height potential and can produce significant psychological distress for patients. We examined effects of treatment with long-acting gonadotropin-releasing hormone(GnRH) agonist on somatic and skeletal growth in patients with central precocious puberty(CPP). MATERIALS & METHODS:Two male and seven female patients were diagnosed as having central precocious puberty(CPP) on the basis of onset age of secondary sexual characteristics, bone age, results of GnRH stimulation test and levels of sex hormones. They were treated with Triptorelin or Leuprorelin acetate(80-100ug/kg, IM every 4 weeks) for 1 year. The patients have been analyzed in terms of changes in auxological parameters including height velocity(HV), HV SDS CA, height SDS CA, height SDS BA and predicted adult height(PAH) SDS before and 1 year after treatment with GnRH agonist.
RESULTS
The growth velocity a year after treatment was decreased to 4.1+/-0.9 from 7.5+/-1.2cm/year(P<0.01) and the height velocity standard deviation score(SDS) for chronologic age decreased to -1.6+/-0.4 from 2.8+/-0.8(P<0.01). The height SDS for chronologic age was increased to 2.0+/-0.7 from 3.8+/-1.0 a year after treatment (P<0.01). However, no significant difference were observed in height SDS for bone age(-1.9+/-0.2 from -2.1+/-0.3)(p>0.05) and predicted adult height SDS(-2.2+/-0.5 from -2.3+/-0.4)(p>0.05) one year after treatment.
CONCLUSION
We observed a remarkable growth deceleration a year after treatment with GnRH agonist in CPP patients. However, the results of this study shows no benefit of GnRH agonist treatment in improving predicted adult height. It is still not clear whether GnRH agonist treatment will eventually help the patients with CPP achieve a final adult height within the range of their genetic target height or not. Further extensive long-term study using strict selection criteria for GnRH agonist treatment is required to address this issue.