Effects of gonadotropin-releasing hormone analogs on height in girls with idiopathic central precocious puberty

Abstract

Objective The purpose of this study was to evaluate effects of gonadotropin-releasing hormone analogs (GnRHa) on improvement of predicted adult height (PAH) in girls with idiopathic central precocious puberty (ICPP) initiating treatment at age of eight years or over and analyze its related factors.Methods Forty-nine girls with ICPP aged eight years and over were treated with GnRHa for ( 17.4 ±5.6) months initiating at age of (9.3 ± 0.6) years during 2005 and 2008.They were followed-up every three to six months to evaluate its effects on growth velocity (GV), height standard deviation score for chronological age (HtSDS-CA), height SDS for bone age (HtSDS-BA), PAH, and so on, as well as their related factors.Results PAH increased after GnRHa treatment, from ( 157.7 ± 4.5) cm six months after treatment to ( 159.2 ±4.4) cm 12 months after treatment, and to ( 160.8 ±5.0) cm by the end of treatment from ( 155.5 ±5.1 ) cm at its initiation (P ＜0.01 ).There was significant difference in PAH by the end of treatment and target height (TH) [( 157.6 ±3.4) cm].HtSDS-BA increased since six months after GnRHa treatment, from ( -0.64 ±0.68) six months to ( -0.52 ±0.70) 12 months after it and ( -0.36 ±0.68)by the its end, all significantly different from ( - 0.94 ± 0.68 ) that at the initiation of treatment ( P ＜0.01 ).There was no significant difference in HtSDS-CA before and after treatment.GV decreased from the initiation (6.3 ± 1.3) cm/yr to (4.8 ± 1.5) cm/yr by the end of treatment ( P ＜ 0.01 ).No significant association between PAH and age of the initiation of treatment and between PAH and age by the end of treatment were found (P ＞ 0.05 ).But, PAH reversely correlated with bone age, and positively correlated with HtSDS-CA, HtSDS-BA, GV, TH and length of treatment ( P ＜ 0.01 ).Conclusions GnRHa can remarkably improves PAH in girl with ICPP.PAH mainly correlates with HtSDS-BA, TH and GV at the initiation and the end of treatment. Key words: Puberty, precocious; Body height; Gonadotropin-releasing hormone analogs