Objective: Gonadotropin-releasing hormone agonist (GnRHa) treatment improves the potential for gaining height in patients with central precocious puberty (CPP). However, most studies have focused on girls because CPP in boys is relatively rare. Therefore, we aimed to determine the effect of GnRHa treatment on auxological outcomes in boys with CPP.
Methods: Eighty-five boys with CPP were treated with leuprolide or triptorelin acetate 3.75 mg over 2 years. Anthropometry, bone age, sexual maturity rating, and predicted adult height (PAH) were assessed every 6 months. Furthermore, 20 boys were followed up after treatment discontinuation until achievement of the final adult height (FAH).
Results: The mean chronological age (CA) and bone age (BA) of the patients with CPP at treatment initiation were 9.5 ± 0.5 years and 11.7 ± 0.9 years, respectively. The mean duration of treatment was 2.87 ± 0.63 years. The PAH at treatment initiation was 172.1 cm (-0.23 ± 1.05 PAH standard deviation score). The PAH at treatment discontinuation (176.2 ± 6.6 cm) was significantly higher than the pretreatment PAH. In addition, the mean final adult height in the 20 boys who were followed up after discontinuation of treatment was 173.4 ± 5.8 cm, which was significantly higher than the initial PAH (170.1 ± 4.5 cm; p = 0.006). In multivariate analysis, the height gain (the difference between the FAH and PAH at treatment initiation) significantly correlated with the target height.
Conclusion: Long-term GnRHa treatment significantly improved the growth potential and FAH in boys with CPP.