Increased visceral adipose tissue is associated with increased circulatinginsulin and decreased sex hormone binding globulin levels in massively obese adolescent girls

The current study was designed to examine the relationship between body fat distribution, as evaluated by anthropometry and magnetic resonance imaging (MRI), and circulating insulin, sex hormone and SHBG levels in obese adole scent girls. Twenty-nine obese adolescent girls, aged 12.6-16.9 years with a mean BMI of 30.51 +/- 1.86 participated in this study. All girls had brea st stage B4-5 and pubic hair stage P4-5. Percent obesity and BMI as indices of being overweight were calculated; the waist-to-hip ratio (WHR) and the waist-to-thigh ratio (WTR) were calculated to obtain two anthropometric ind ices for the pattern of body fat distribution. The areas of visceral (VAT) and subcutaneous adipose tissue (SAT) were evaluated by MRI at the L4-L5 le vel. Serum concentrations of total T, DHEAS, 17 beta -estradiol, progestero ne and SHBG were measured. Plasma glucose and insulin concentrations were e valuated during an oral glucose tolerance test. WHR was the only anthropome tric parameter that was significantly associated with the area of VAT. Insu lin level showed correlation with both WHR and the area of VAT; no correlat ion was found between insulin levels and WTR. Both WHR and VAT were negativ ely correlated with serum DHEAS level and positively correlated with T leve l. There were strong negative correlations between serum SHBG level and the area of VAT and WHR. Inverse correlation was found between serum SHBG leve l and insulin. Serum 17 beta -estradiol and progesterone levels showed no s ignificant correlation with all the patterns of body fat distribution. SAT was not significantly correlated with both anthropometric parameters and an y of the sex hormones evaluated. We can draw two main conclusions. Firstly, in massively obese adolescent girls, the WHR seems to be a good indicator for the accumulation of VAT, and abdominal obesity, rather than adiposity p er se, appears to be related to biochemical complications. Secondly, increa sed upper body adiposity and, in particular, the intra-abdominal fat area a re associated with increased insulin levels in massively obese adolescent g irls. The associated reductions in SHBG and DHEAS levels represent an early general risk factor for the development of metabolic and cardiovascular di seases in this population, as previously described for obese adult women. ( J. Endocrinol. Invest. 24: 438-444, 2001) (C) 2001, Editrice Kurtis.