Initial growth deceleration during GnRH analogue therapy for precocious puberty.

OBJECTIVES

To compare the efficacy of goserelin and leuprolide on initial deceleration of growth and weight gain during the first 12 months of GnRH analogue treatment for precocious puberty.

DESIGN

Retrospective cohort analysis.

PATIENTS: Forty children with precocious puberty treated with either goserelin or leuprolide (33 females, mean age 7.3 and 7.7 years, respectively, at the start of treatment).

MEASUREMENTS: The primary outcomes were baseline-to-6-months and 6-months-to-12-months change in height standard deviation score (SDS) and body mass index (BMI). Relative tall stature was calculated as the difference between height SDS and mid-parental height (MPH) SDS at baseline.

RESULTS

Goserelin and leuprolide were associated with similar suppression of serum LH during the first 12 months of treatment (P = 0.62). Greater relative tall stature was strongly associated with more advanced bone age, greater BMI SDS and with greater reduction in height SDS in the first 6 months. Adjusted for relative tall stature, goserelin therapy was associated with significantly greater suppression of growth than leuprolide (P = 0.025) in the first 6 months of treatment, with no subsequent change in the second 6 months. A similar, significant increase in BMI was seen with both analogues.

CONCLUSIONS

Both GnRH analogues were associated with effective biochemical suppression of puberty; however, goserelin was more effective at reducing linear growth during the first 6 months. Relative tall stature was a major determinant of the initial response to treatment.