The impact of gender, puberty and body mass on reference values for urinary growth hormone (GH) excretion in normally growing non-obese and obese children

OBJECTIVE: There is a lack of normal reference data on urinary GH (u- GH) excretion in children, We have investigated the impact of age, gender, pubertal development and body mass on reference values for u-GH excretion in normally growing non-obese and obese children. STUDY DESIGN: u-GH levels were evaluated in 1153 healthy normal children (aged 5-14) and in 684 obese children (body mass index, BMI:>75th). u-GH levels (ng/8 h) were determined by ELISA as the mean value of three consecutive first morning voidings. RESULTS: Reference values (5-95th centile) for u-GH excretion in obese and non-obese children of both sexes are reported. In normal prepubertal children median u-GH levels were relatively stable and superimposable in the two sexes; subsequently, u-GH levels increased, reaching a peak Value at 13 years in both sexes. Significant increments (P