Tengvall Marja, Ellegård Lars, Malmros Vibeke, Bosaeus Niklas, Lissner Lauren, Bosaeus Ingvar
Department of Clinical Nutrition, Sahlgrenska University Hospital, Sahlgrenska Academy at University of Gothenburg, Goteborg, Sweden.
Clin Nutr. 2009 Feb;28(1):52-8. doi: 10.1016/j.clnu.2008.10.005. Epub 2008 Nov 17.
BACKGROUND & AIMS: To validate the bioelectrical impedance spectroscopy (BIS) model against dual-energy X-ray absorptiometry (DXA), to develop and compare BIS estimates of skeletal muscle mass (SMM) to other prediction equations, and to report BIS reference values of body composition in a population-based sample of 75-year-old Swedes.
Body composition was measured by BIS in 574 subjects, and by DXA and BIS in a subset of 98 subjects. Data from the latter group was used to develop BIS prediction equations for total body skeletal muscle mass (TBSMM).
Average fat free mass (FFM) measured by DXA and BIS was comparable. FFM(BIS) for women and men was 40.6 kg and 55.8 kg, respectively. Average fat free mass index (FFMI) and body fat index (BFI) for women were 15.6 and 11.0. Average FFMI and BFI for men were 18.3 and 8.6. Existing bioelectrical impedance analysis equations to predict SMM were not valid in this cohort. A TBSMM prediction equation developed from this sample had an R(2)(pred) of 0.91, indicating that the equation would explain 91% of the variability in future observations.
BIS correctly estimated average FFM in healthy elderly Swedes. For prediction of TBSMM, a population specific equation was required.
对照双能X线吸收法（DXA）验证生物电阻抗光谱法（BIS）模型，开发骨骼肌质量（SMM）的BIS估计值并与其他预测方程进行比较，以及报告基于人群的75岁瑞典人样本的身体成分BIS参考值。
对574名受试者采用BIS测量身体成分，对98名受试者的一个子集同时采用DXA和BIS测量。后一组的数据用于开发全身骨骼肌质量（TBSMM）的BIS预测方程。
DXA和BIS测量的平均去脂体重（FFM）具有可比性。女性和男性的FFM（BIS）分别为40.6千克和55.8千克。女性的平均去脂体重指数（FFMI）和体脂指数（BFI）分别为15.6和11.0。男性的平均FFMI和BFI分别为18.3和8.6。现有的预测SMM的生物电阻抗分析方程在该队列中无效。从该样本开发的TBSMM预测方程的R（2）（pred）为0.91，表明该方程将解释未来观察中91%的变异性。
BIS正确估计了健康老年瑞典人的平均FFM。对于TBSMM的预测，需要一个针对特定人群的方程。
