BMI and objectively measured body fat distribution in pre-pubertal children
Involverte ansatteM. Dencker 1, O. Thorsson 1, C. Lindén 1, P. Wollmer 1,
L.B. Andersen 2, M.K. Karlsson 1.
Submitted to Acta Pediatrica jan 2006.
BeskrivelseBody mass index (BMI) is often used as a surrogate measurement for body fat in epidemiological studies. This study explores the association between BMI vs. body fat and body fat distribution assessed by Dual-energy x-ray absorptiometry (DXA) scanning in younger children.
Cross-sectional study of 246 children (138 boys and 108 girls) aged 8 to 11 years from a population-based cohort. DXA was used to quantify abdominal fat mass (AFM), total body fat (TBF) and also total body fat as percentage of body mass (BF%). Body fat distribution was calculated as AFM/TBF.
Results: Univariate correlations between BMI vs. TBF, BF% and AFM (r=0.94, r=0.92, and r=0.93) for boys and (r=0.95, r=0.92, and r=0.95) for girls, respectively (p<0.05 for all r-values). However, significantly lower correlation (p<0.001 for difference in r-values) existed for body fat distribution (r=0.64 and 0.73, respectively).
Conclusion: In this cohort of children, total body fat and abdominal fat masses were closely associated with BMI, suggesting that BMI serves as a god surrogate marker for obesity in population studies. However, a significantly lower correlation existed for BMI vs. body fat distribution, which may be a limitation when BMI is used to study cardiovascular risk factors in epidemiological studies.