BMI and objectively measured body fat and body fat distribution in prepubertal children.
BACKGROUND
Body Mass Index (BMI) is often used as a surrogate estimate of body fat in epidemiological studies. This study explores the association between BMI, body fat and body fat distribution assessed by Dual-Energy X-Ray Absorptiometry (DXA) in younger children.


METHODS
Cross-sectional study of 246 children (138 boys and 108 girls) aged 8-11 years. DXA was used to quantify abdominal fat mass (AFM), total body fat (TBF) and also total body fat as percentage of total body mass (BF%). Body fat distribution was calculated as AFM/TBF.


RESULTS
We found close 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 between the r-values) existed for body fat distribution (r = 0.64 for boys and 0.73 for girls).


CONCLUSIONS
Percentage body fat, TBF and AFM were all closely associated with BMI, suggesting that BMI serves as a good 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.
Dencker
Magnus
M
Department of Clinical Sciences, Malmö, Lund University, Sweden. magnus.dencker@skane.se
Thorsson
Ola
O
Lindén
Christian
C
Wollmer
Per
P
Andersen
Lars B
LB
Karlsson
Magnus K
MK
D000273:Adipose Tissue / Q000502:physiology*; D000886:Anthropometry / Q000379:methods; D050218:Body Fat Distribution / Q000706:statistics & numerical data*; D015992:Body Mass Index; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D011627:Puberty / Q000502:physiology; D012737:Sex Factors; D013548:Sweden / Q000453:epidemiology