[Effects of gonadotropin releasing hormone analog and growth hormone on height in girls with idiopathic central precocious puberty].

OBJECTIVE

To determine the effect of gonadotropin releasing hormone agonist (GnRHa), by itself alone or in combination with recombinant human growth hormone (rhGH), on height in young girls (bone age≥10 years) with idiopathic central precocious puberty (ICPP).

METHODS

Eighty girls with ICPP (9.0±0.7 years old) from six medical centers across Southeast and Southwest China participated in this study. They were allocated to treatment with GnRHa+rhGH (n=31) and GnRHa (n=49) respectively. Girls in the GnRHa+rhGH group (bone age 11.18 ±0.53 years) were treated with GnRHa for 25.29±6.92 months and rhGH for 12.87±7.02 months. Girls in the GnRHa group (bone age 11.03 ±0.50 years) were treated with GnRHa for 25.96±8.95 months. The height standard deviation for bone age (HtSDS-BA), predicted adult height, near-adult height and net height increase before and after treatment were recorded for girls in both groups.

RESULTS

HtSDS-BA was significantly improved after treatment for both groups (P<0.01) and the HtSDS-BA value was superior in the GnRHa+rhGH group over the GnRHa group (P<0.01). Values in near adult height (157±6 cm vs 157±4 cm), net height increase after treatment (4.68 cm vs 3.89 cm), and predicted adult height after drug withdrawal (161±5 cm vs 158±5 cm) were higher in the GnRHa+rhGH group than the GnRHa group, but the differences were not significant.

CONCLUSIONS

Both GnRHa plus rhGH and GnRHa alone can improve the near adult height in girls with ICPP with a bone age ≥10 years to a similar extent. Adult height predicted based on bone age in ICPP girls following drug withdrawal is usually overestimated and precautions should be taken when this parameter is used.