Growth and Growth-determining Factors in Girls with Idiopathic Central Precocious Puberty Treated with Long-acting Luteinizing Hormone-Releasing Hormone Analogue

Shin, Choong Ho; Hwang, Jin Soon; Lim, Jung Sub; Kim, Se Young; Shim, Kye Shik; Yang, Sei Won; Yu, Jee Suk

Abstract

PURPOSE
In idiopathic central precocious puberty(CPP), characterized by premature but otherwise normal puberty, the early onset of the pubertal growth spurt with increased height velocity results in premature epiphyseal closure with reduced final height. We examined the growth and growth-determining factors in female patients with CPP treated with a long-acting luteinizing hormone-releasing hormone analogue(Tryptorelin).
METHODS
Ten female patients who were diagnosed as idiopathic precocious puberty were treated with Tryptorelin(0.06mg/kg, IM every 4 weeks) for 2 years. We evaluated the patients into two groups(Group A, 4 cases, predicted adult height before treatment were less than 150cm; Group B, 6 cases, predicted adult height before treatment were 150cm or greater), and analysed the growth and its determing factors.
RESULTS
In total patients, the growth velocity during the second year were decreased to 4.1+/-1.9 from 5.7+/-2.2/yr during the first year(p>0.05) and no significant difference was found in predicted adult height(PAH) before and after 2 years of treatment(152.3+/-6.7 vs. 1453.9+/-6.8cm). The difference between the PAH before and after 2 years of treatment was not correlated with age, bone age, PAH, height standard deviation score(Ht SDS) before treatment, but correlated with difference between the PAH before and after 1 year of treatment(r=0.89310, P=0.0005). The mean Ht SDS for bone age in group A were significantly lower than those in group B(P<0.05). In group A, the mean PAH increased from 147.0+/-1.9 to 153.7+/-3.7cm during two years of treatment, but no difference in PAH was found in group B. So PAH were similar in two groups(154.1+/-8.7 vs. 153.7+/-3.7cm) after second year. The mean difference between bone age and chronological age decreased from 4.5+/-1.3 to 3.0+/-1.3 years in group A(P<0.05).
CONCLUSION
Long-term Tryptorelin treatment is more effective in girls with idiopathic central precocious puberty, whose PAH before treatment were below 150cm. If PAH before treatment is 150 cm or greater or increase in PAH during the first year of treatment is poor, this treatment modality might be useless in terms of improved growth.