UC San Diego

Objectives

Gonadotropin-releasing hormone agonist treatment is important for optimal growth in girls with central precocious puberty (CPP). Data are lacking regarding benefit to height outcome when treatment is started after chronological age (CA) of 7 years, and if continued beyond CA of 10 years or bone age (BA) of 12 years.

Methods

Forty-eight girls with CPP were treated with monthly leuprolide depot. Change in predicted adult height (PAH) during treatment was assessed. Changes in PAH and growth velocity were compared between girls initiating treatment at CA <7 vs. ≥7 years, and BA ≥12 vs. BA <12 years.

Results

Mean baseline CA was 6.8 years, BA, 10.2 years; and PAH, 156.4 cm. BA/CA ratio decreased from pretreatment values, averaging 1.5 to 1.2 at the end of treatment. Proportion of girls with >5 cm PAH change during treatment was similar, and PAH increased throughout treatment in most girls, regardless of age at treatment initiation. PAH continued to increase in 16/19 girls who continued treatment after BA of 12 years, and also in 16/22 girls who continued treatment after CA of 10 years.

Conclusions

PAH improved in most girls who initiated treatment after CA of 7 years. It continued to improve in most girls with longer treatment, even past BA of 12 years or CA of 10 years, which suggests that no absolute CA or BA limit should define initiation or end of treatment. Treatment plans need to be individualized, and neither treatment initiation nor cessation should be based on BA or CA alone.