Supplementary Material for: Determinants of Advanced Bone Age in Childhood Obesity

<i>Background:</i> Childhood obesity is associated with advanced bone age (BA). Previous studies suggest that androgens, oestrogens, sex hormone-binding globulin, and insulin are responsible for this phenomenon, but results are contradictory and might be biased by confounders. We aim to elucidate this matter by applying a multivariate approach. <i>Method:</i> We performed a correlation analysis of BA standard deviation score (SDS) with age- and sex-specific SDS for androgens, oestrogens, and with indicators of insulin secretion derived from oral glucose tolerance testing, in a group of obese children. A multivariate analysis was performed to investigate which parameters were independently predictive of BA SDS. <i>Results:</i> In this cohort (<i>n</i> = 101; mean age 10.9 years; mean BA 11.8 years; mean BMI SDS 3.3), BMI SDS was significantly correlated to BA SDS (<i>r</i> = 0.55, <i>p</i> < 0.001). In a regression analysis in the total cohort (<i>B</i> = 0.27, <i>p</i> < 0.001) as well as in females (<i>B</i> = 0.34, <i>p</i> = 0.042), males (<i>B</i> = 0.31, <i>p</i> = 0.006), and pubertal children (<i>B</i> = 0.32, <i>p</i> = 0.046), dehydroepiandrosterone sulphate (DHEAS) showed a positive, independent association with BA SDS. No association with indicators of insulin secretion was found. <i>Conclusion:</i> BMI SDS is highly correlated to BA SDS in obese children. Increased DHEAS has a central role in advanced BA in obese children.