Long-term outcomes of gonadotropin-releasing hormone agonist treatment in girls with central precocious puberty

Purpose: This study aimed to examine the effects of gonadotropin-releasing hormone agonist (GnRHa) treatment on final height outcomes in girls with idiopathic central precocious puberty (CPP) from the start of treatment to their postmenarche visit. Methods: We conducted a retrospective analysis of 200 girls with idiopathic CPP who received GnRHa therapy, focusing on auxological and clinical outcomes at treatment initiation, treatment completion, and the last, postmenarche visit. Results: The mean chronological age (CA) at GnRHa treatment initiation was 8.24 +/- 0.73 years. The mean duration of GnRHa treatment was 3.12 +/- 0.81 years. The average age at menarche was 12.73 +/- 0.56 years, occurring a mean of 17.15 +/- 5.52 months after completing GnRHa therapy. The predicted adult height (PAH) standard deviation score (SDS) after menarche (0.48 +/- 0.99) was significantly greater than before treatment (-1.33 +/- 1.46) (P<0.001). Factors including greater bone age advancement (P<0.001), lower height SDS for CA at treatment initiation (P<0.001), and higher midparental height SDS (P=0.001) were positively associated with an increase in PAH SDS at the last visit. However, near-final height and the increase in PAH SDS at the last visit were not significantly different between patients who received early treatment (<8 years) and those who received later treatment (8-9 years). Conclusion: GnRHa treatment improved the final height outcomes in all girls with CPP, including those treated between 8 and 9 years of age.