ESPE Abstracts

Aim: Central precocious puberty (CPP) is defined as premature activation of the hypothalamic–pituitary–gonadal (HPG) axis before the age 8 in girls. Precocious puberty starting at a very young age causes a severe loss in height potential and should be treated with gonadotropin releasing hormone agonists (GnRHa). However, there are controversial results about the benefit of the GnRHa treatment in girls whose CPP is initiated near the age 8. This study evaluated the effectiveness of GnRHa treatment on final height of 160 girls with CPP in this specific age group. Moreover, it has been also investigated if this therapy had any negative effect on bone health.

Method: This retrospective study was conducted on 117 girls with CPP who were diagnosed near the age 8 (7-9 years old). The girls, who’s the treatment were initiated between the ages 8-9 years (n=71) and 7-8 years (n=46) were included to the group 1 and 2 respectively. Predicted height (PAH), target height (TH) were calculated at the beginning of the therapy according to medical records and final adult heights (FAH) were obtained also from the records. Age of onset of the treatment, the duration of GnRHa therapy, anthropometric measures of the children and bone mineral density z-scores (n=52) after the treatment were also recorded. Girls’ PAH, TH and FAH were also compared between groups. Paired t test was also performed to assess the difference between PAH and FAH.

Results: The mean age of the girls at the beginning of the treatment was 8.59±0.27 in group 1 and 7.50±0.47 in group 2. The durations of GnRHa therapy were 1.97±0.54 and 2.91±0.61 in group 1 and 2 respectively. The TH (160,53±5,49 vs160,57±4,94), PAH (158,72±5,23 vs 158,35±5,57) and FAH (162,42±5,32 vs 162,14±5,70) were not statistically different between groups. Multiple regression analysis demonstrated that major determinant factor of the FAH was baseline height SDS (Beta: 0.572, P<0.001). However, FAH was improved approximately 4 cm from the PAH in both groups (P<0.001). There were not any girls with osteoporosis after treatment. However, 4/52 girls had a BMD z-score between -1 and -2.

Conclusion: GnRHa may improve FAH even the treatment is delayed after the age 8 without a serious negative effect on BMD. However, as this improvement is limited for this age group, the therapy option should be individualized and should not be considered for all children.