Relationships of IGF-I and Androgens to Skeletal Maturation in Obese Children and Adolescents

UNLABELLED: IGF-I and androgens are postulated to accelerate skeletal maturation in obese children. METHODS: We studied weight status (BMI-SDS), height-SDS, IGF-I, cortisol, DHEA-S, and testosterone in 356 obese children (aged 4-15 years; 54% females) and correlated them to differences between bone age and chronological age (deltaBA-CA). Direct multivariate linear regression analyses were conducted for the dependent variable deltaBA-CA, including BMI, age, gender, pubertal stage, IGF-I-SDS, cortisol, DHEA-S, and testosterone as independent variables separately in prepubertal and pubertal girls, and prepubertal and pubertal boys. RESULTS: Height-SDS (r = 0.52), IGF-I (r = 0.33), and IGF-I-SDS (r = 0.36) were significantly (p < 0.001) correlated to deltaBA-CA. In multiple regression analyses, BMI and IGF-I-SDS were significantly positively (p < 0.001) correlated to deltaBA-CA independently of gender and pubertal stage. Testosterone was significantly positively correlated to detaBA-CA only in prepubertal girls (p = 0.035). CONCLUSIONS: Since IGF-I concentrations were positively associated to deltaBA-CA independently of pubertal stage and gender, we put forward the hypothesis that this hormone may contribute to acceleration of skeletal maturation in obese children.