Objective
To investigate the effects of gonadotropin-releasing hormone analogue (GnRHa) on body mass index (BMI) and bone metabolism markers in girls with idiopathic central precocious puberty (ICPP).
Methods
Totally 100 ICPP girls admitted to our hospital from January 2015 to January 2016 were selected as the study group, and 100 healthy check-up girls in our hospital during the same period were selected as the control group. The observation group was treated with triptorelin hydrochloride for 1.5 years. Up to June 2018, the average follow-up time was (1.1±0.3) years. The age, bone age, BMI, overweight rate and obesity rate of the girls in the observation group at the beginning, end of treatment and at the time of reaching lifelong height were recorded. The levels of procollagen type I amino-terminal peptide(P1NP), osteocalcin N-terminal midmolecular fragment(N-MID) and β-collagen degradation product(β-CTX) were recorded before and 2 years after treatment in the observation group and in the control group.
Results
The age, bone age and BMI at the end of treatment in the observation group were higher than those at the beginning of treatment, and the difference was statistically significant (P<0.05); the age and bone age at reaching the lifelong height were higher than those at the beginning of treatment in the observation group(P<0.05), while BMI was similar(P>0.05). In the observation group, the age and bone age at the time of reaching lifelong height were higher than those at the time of discontinuation of treatment, while BMI was lower(P<0.05). Before treatment, the levels of P1NP and N-MID in the observation group were significantly higher than those in the control group(P<0.05), but there was no significant difference in the levels of β-CTX between the two groups (P>0.05). After treatment, the levels of P1NP and N-MID in the observation group were significantly lower than those before treatment and the difference was statistically significant(P<0.05); after treatment, the level of β-CTX was not significantly different from that before treatment(P>0.05).
Conclusion
GnRHa can effectively inhibit the hyperactivity of osteoblasts in girls with ICPP, and has no significant effect on the function of osteoclasts. Although the BMI value of the patients increases during the treatment, it will return to normal level after the treatment.