Final Height in Girls with Central Idiopathic Precocious Puberty Treated with Gonadotropin-Releasing Hormone Analog and Oxandrolone

Abstract

GnRH analogs (GnRHa) are considered the treatment of choice for central precocious puberty (CPP). During GnRHa administration, the suppression of the pituitary-gonadal axis results in decreased rates of linear growth and skeletal maturation and in improved adult height. However, in some patients, the growth deceleration is so marked that the expected improvement in predicted adult height is not achieved. The objective of this study was to assess whether the addition of oxandrolone (Ox) may affect the height outcome of patients with CPP and growth deceleration during GnRHa treatment. This was an open-label, clinical study. The study was performed at a pediatric endocrinology referral clinic. Twenty patients with CPP and marked growth deceleration during GnRHa treatment were studied. Treatment consisted of GnRHa (Leuprorelina, 3.75 mg im every 28 d) alone (10 patients) or in combination with Ox (0.06 mg/kg.d by mouth) (10 patients). The main outcome measure was the patients' adult height. The adult height of the patients treated with GnRHa plus Ox was significantly higher than pretreatment predicted adult height (162.6 +/- 2.3 vs. 154.8 +/- 1.7 cm, mean +/- sem; P < 0.05) and target height (162.6 +/- 2.3 vs. 158.0 +/- 1.9; P > 0.05). Patients treated with GnRHa alone reached an adult height similar to the pretreatment predicted adult height (151.9 +/- 1.2 vs. 155.4 +/- 2.1 cm) but significantly lower than target height (151.9 +/- 1.2 vs. 156.6 +/- 1.4 cm; P < 0.005). No side effects were recorded in either group of patients. Combined GnRHa and Ox therapy is a viable treatment option for children with CPP and marked growth deceleration during treatment with GnRHa alone.