Dose of LHRH Analog and Growth Velocity Influence Predicted Final Height in Girls with Central Precocious Puberty

Clinical variables that influence final height were analyzed in 27 girls with central precocious puberty treated with LHRH analog (TAP-144-SR: leuprorelin acetate). The patients were treated for a mean treatment period of 210.4 weeks. Plasma IGF-I levels did not change significantly during treatment. The predicted final height by projected height standard deviation score (SDS) for bone age at final estimation correlated positively with the average growth velocity during LHRH analog treatment. The mean growth velocity showed a significant negative correlation with the mean dose of LHRH analog; such a tendency was also clearly observed in patients who began to receive treatment after the age of 6 years. Although estradiol levels did not show any correlation with height velocity because of the low sensitivity of estradiol measurement, changes in plasma estradiol levels may contribute to changes in growth velocity, especcially in patients of pubertal bone age. To improve the final height prognosis in precocious puberty, it is recommended that LHRH analog be used at the minimum effective dose to maintain growth velocity during treatment.