Determinants of Advanced Bone Age in Childhood Obesity

Abstract

Background: 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.

Method: 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.

Results: In this cohort (n = 101; mean age 10.9 years; mean BA 11.8 years; mean BMI SDS 3.3), BMI SDS was significantly correlated to BA SDS (r = 0.55, p < 0.001). In a regression analysis in the total cohort (B = 0.27, p < 0.001) as well as in females (B = 0.34, p = 0.042), males (B = 0.31, p = 0.006), and pubertal children (B = 0.32, p = 0.046), dehydroepiandrosterone sulphate (DHEAS) showed a positive, independent association with BA SDS. No association with indicators of insulin secretion was found.

Conclusion: BMI SDS is highly correlated to BA SDS in obese children. Increased DHEAS has a central role in advanced BA in obese children. .

Keywords: Androgens; Bone age; Dehydroepiandrosterone; Insulin; Obesity.

Fig. 1

Flowchart with reasons of exclusion.

Fig. 2

a Association between BMI SDS and age (years). b Association between BA (BA) (years) and chronological age (years). c Association between BA SDS and age. d Association between BA SDS and BMI SDS. SDS, standard deviation score; BMI, body mass index; BA, bone age; R², coefficient of deviation. Squares represent males, x's represent females, circles represent males with monogenetic obesity, and asterisks represent females with monogenetic obesity.