Author
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Mitchell, Alva |
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Submitted to: Pediatric Research
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/28/2010 Publication Date: 3/20/2011 Citation: Mitchell, A.D. 2011. Validation of QMR body composition analysis for infants. Pediatric Research. 69(4):330-335. Interpretive Summary: Accurate assessment and tracking of infant body composition is useful in evaluating the amount and quality of weight gain, which can provide key information in both clinical and research settings. Body composition analysis can be used to monitor and evaluate infant growth patterns, efficacy of nutritional and medical interventions, progression of chronic disease, and recovery from malnutrition. A study was conducted to validate the use of a quantitative magnetic resonance (QMR) device for measuring the body composition of infants and neonates weighing less than 12 kg using the pig as a model. Body composition was assessed by QMR, dual-energy X-ray absorptiometry (DXA), and whole-body chemical analysis (CA) of carcass for lipid and water content. QMR measures of fat mass, lean mass and total body water were highly and significantly correlated with CA of carcass. In terms of accuracy, QMR overestimated fat mass by 4.7 %, overestimated lean mass by 2.1 %, and underestimated total body water by 3.1 %. This study concludes that QMR provides precise and accurate measures of FM, LM and TBW in piglet weighing up to 12 kg. These results suggest that QMR can provide valuable body composition data in longitudinal studies in infants. Technical Abstract: A study was conducted to validate the use of a quantitative magnetic resonance (QMR) device for measuring the body composition of infants and neonates weighing less than 12 kg using the pig as a model. A total of 25 piglets weighing between 2 and 12 kg were studied. Body composition was assessed by QMR, dual-energy X-ray absorptiometry (DXA), and whole-body chemical analysis (CA) of carcass for lipid and water content. The precision, mean standard deviation of repeated measurements, of QMR to estimate fat mass (FM), lean mass (LM), and total body water (TBW) for five consecutive scans with reposition was 12.5, 32.0 and 36.0 grams respectively. QMR measures of FM, LM and TBW were highly and significantly correlated with CA of carcass. In terms of accuracy, mean difference between QMR and CA (percent of mean value for CA), QMR overestimated FM by 40 g (4.7 %), overestimated LM by 114.9 g (2.1 %), and underestimated TBW by 134.6 g (3.1 %). This study concludes that QMR provides precise and accurate measures of FM, LM and TBW in piglet weighing up to 12 kg. These results suggest that QMR can provide valuable body composition data in longitudinal studies in infants. |
