Longitudinal assessment of auxological parameters, adult height outcome and its determinants in leuprolide-treated Indian girls with idiopathic central precocious puberty

Objectives: To assess auxological parameters, adult height outcome and its determinants in Indian girls with idiopathic central precocious puberty (iCPP) treated with gonadotropin-releasing hormone analogues (GnRHa).

Methods: Retrospective study. Inclusion: data on girls with iCPP from initiation to stopping GnRHa (n=179). Exclusion: boys, peripheral, organic central precocity.

Results: Mean age of starting GnRHa: 8.2± 1.1 years, duration: 2.8± 1.2 years. 11.7 % had attained menarche at first presentation. The difference between bone (BA) and chronological (CA) ages reduced significantly from 2.6± 0.9 years (onset) to 1.6± 0.8 years (cessation). Weight, BMI Z-scores increased (p<0.01), height Z-scores decreased (0.8 vs. 0.6; p<0.01), predicted adult height (PAH) and Z-scores improved by 3.5 cm, 0.5 SDS following treatment (p<0.01). Overweight/obese girls (vs. normal BMI) were taller, with more advanced BA at starting (height Z-score: 0.7 vs. 1.0, BA-CA: 2.2 vs. 2.9 years), stopping (height Z-score: 0.5 vs. 0.9, BA-CA: 1.4 vs. 1.9 years) treatment, but showed no difference in PAH at starting, stopping treatment. Adult height data (n=58) revealed 1.9 cm gain above target height. Adult height Z-scores significantly exceeded target height Z-scores (p<0.01). Mean adult height (157.1± 5.8 cm) crossed PAH at starting treatment (155.9± 6.4 cm) but remained 1.6 cm lesser than PAH at cessation. Adult weight, BMI Z-scores (-0.2± 1.3, -0.1± 1.2) were significantly lower (p<0.01) than those at stopping GnRHa. Height gain adjusted for age at starting GnRHa correlated negatively with height, weight, BMI, Tanner-staging, BA, FSH, Estradiol at treatment onset, BA at cessation, and correlated positively with treatment duration.

Conclusions: GnRHa treatment in Indian girls with iCPP resulted in improved PAH, decelerated bone age advancement and growth velocity. Most girls achieved adult height within target range, surpassing PAH at treatment initiation. Lesser anthropometric, sexual, skeletal maturity, lower baseline FSH, estradiol, longer treatment duration, less advanced BA at stopping GnRHa may translate into better adult height outcomes.