ARS | Publication request: BMI is not a good indicator for metabolic risk in adolescent girls

Submitted to: Acta Paediatrica
Publication Type: Abstract Only
Publication Acceptance Date: March 2, 2009
Publication Date: October 10, 2009
Citation: Van Der Heijden, G.J., Wang, Z., Chu, Z., Sauer, P.J.J., Sunehag, A.L. 2009. BMI is not a good indicator for metabolic risk in adolescent girls [abstract]. Acta Paediatrica. 98:255(Suppl.460).

Technical Abstract: BMI (kg/m2) does not provide information about body fat percentile.Adolescents with BMI <85th percentile for age are considered lean and at low risk for metabolic complications. Adolescent girls with low BMI can have high body fat percentile. We hypothesized that these girls are already insulin resistant. Twenty-one post-pubertal adolescent girls (13–17 year) were studied: 9 had low BMI (<85th percentile), high body fat (>27%) (LH) (22.5 +/- 0.6 kg/m2; 32.1 +/- 0.7% fat), 4 low BMI, low body fat (<27%) (LL) (19.1 +/- 0.9 kg/m2; 24.3 +/- 1.1%fat); and 8 were obese (BMI>95th percentile), body fat (>30%) (O (33.4 +/- 1.6 kg/m2; 42.0 +/- 1.1% fat). Blood samples were obtained after an overnight fast. Body fat% was measured by DXA and subcutaneous, visceral and hepatic fat by MRI/MRS. The higher body fat% in LH compared to LL girls was accounted for by increased subcutaneous and visceral fat content while hepatic fat was not different. Obese subjects had higher subcutaneous, visceral and hepatic fat content than both LH and LL subjects. Nonetheless, insulin resistance measured by HOMA-IR was not significantly different in LH as compared to O subjects (2.7 +/- 0.3 vs. 4.6 +/- 1.1) while both were higher than that of LL subjects(1.5 +/- 0.1)(P < 0.05). Leptin concentrations were higher in O than in LH subjects (P < 0.01), which in turn were higher than in LL subjects (P < 0.01). Adiponectin was similar in LH and LL subjects but higher than in O subjects. Despite low BMI, adolescent girls might have high body fat%, which is already associated with insulin resistance comparable to that of obese subjects.