Accuracy of quantitative magnetic resonance and eight-electrode bioelectrical impedance analysis in normal weight and obese women

作者：Bosaeus Marja^*; Karlsson Therese; Holmang Agneta; Ellegard Lars

来源：Clinical Nutrition, 2014, 33(3): 471-477.

DOI：10.1016/j.clnu.2013.06.017

• Body composition
• Obesity
• Quantitative magnetic resonance
• Bioelectrical impedance analysis
• Air displacement plethysmography

Background & aims: Quantitative magnetic resonance (QMR) has previously been shown to both overestimate and underestimate average fat mass (FM) in humans. Eight-electrode bioelectrical impedance analysis (BIA) has previously been found biased as well as successfully validated. We report cross-sectional accuracy of QMR and eight-electrode BIA evaluated with air displacement plethysmography (ADP) as reference method.
Methods: Fat mass and fat free mass (FFM) by QMR and eight-electrode BIA were evaluated against ADP as reference in 38 normal weight and 30 obese women. Total body water estimates by QMR and eight-electrode BIA were compared.
Results: Fat mass was overestimated by QMR (1 +/- 2 kg, p < 0.001) and was underestimated by eight-electrode BIA (1 +/- 3 kg, p = 0.03, Bonferroni adjusted p = 0.29) in normal weight women. Fat mass was underestimated by both QMR (2 +/- 2 kg, p < 0.001) and eight-electrode BIA (9 +/- 3 kg, p < 0.001) in obese women. Fat free mass biases were of similar magnitude but in opposite direction to FM biases. Total body water estimates were larger by eight-electrode BIA compared to QMR (1-10 kg).
Conclusions: Fat mass and FFM by QMR were both biased but in opposite directions in both normal weight and obese women. Eight-electrode BIA FM and FFM estimates were imprecise and biased in obese women. Thus, QMR is more precise and more accurate than eight-electrode BIA for estimating body composition in women, but is not accurate enough to be used for individual single assessment of body composition.

• 出版日期2014-6
• 单位河北医科大学