Abdominal Fat Assessment in Adolescents Using Dual-energy X-ray Absorptiometry

Exercise, Health & Performance Faculty Research Group, Faculty of Health Science, The University of Sydney, Australia.
Journal of pediatric endocrinology & metabolism: JPEM (Impact Factor: 1). 09/2009; 22(9):781-94. DOI: 10.1515/JPEM.2009.22.9.781
Source: PubMed


Abdominal obesity is an increasing problem in adolescents, often persisting into adulthood. Reliable assessment has been restricted to techniques limited by relatively high radiation doses or cost.
To investigate the reliability of several abdominal regions using dual-energy X-ray absorptiometry (DXA), and to assess the construct validity of these methods against metabolic profile.
Inter- and intra-rater precision of two assessors were examined, for fat mass analysis in six different abdominal regions using DXA in overweight/obese and normal weight adolescents. Construct validity was examined in overweight/obese individuals.
All methods had acceptable intra- and inter-rater reliability. Region 1 was most precise in overweight/obese individuals, while Region 6 was most precise in normal weight individuals. In all regions, assessments were less precise in overweight/obese individuals. All regions were equally predictive of insulin outcomes.
Abdominal adiposity can be reliably assessed in adolescents using DXA, and the most precisely assessed regions were identified. All regions predicted insulin outcomes.

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Available from: Tracey W Tsang
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