Intensive Care Unit, Pediatrics Department, Fernandes Figueira Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
Clin Nutr. 2012 Feb;31(1):144-8. doi: 10.1016/j.clnu.2011.08.006. Epub 2011 Aug 26.
BACKGROUND & AIMS: Ethnicity may influence bioimpedance values. The goal of this study was to measure total body impedance vector in infants and pre-school children in Brazil and compare them with those reported in other countries.
We analyzed bioelectrical impedance from a sample of 255 healthy Brazilian children, aged 1-36 months, using the RXc graph method (tetrapolar analysis at 50 kHz frequency). The 95%, 75% and 50% tolerance ellipses were plotted by age group.
The mean impedance vector showed migration across age groups, with progressive higher reactances and lower resistances as age increased. The mean bioimpedance vectors from the present sample of Brazilian children were different from those of European children of the same age ranges.
Our results confirm the importance of defining reference values of total body impedance vector for each country in view of the considerable ethnic diversity among different geographical areas.
种族可能会影响生物阻抗值。本研究的目的是测量巴西婴幼儿的全身阻抗向量，并将其与其他国家的报告进行比较。
我们使用 RXc 图谱法（50 kHz 频率的四极分析）分析了 255 名健康巴西儿童（1-36 月龄）的生物电阻抗。按年龄组绘制 95%、75%和 50%耐受椭圆。
阻抗向量的平均值随着年龄组的变化而迁移，随着年龄的增长，电抗逐渐升高，电阻逐渐降低。本研究中巴西儿童的平均生物阻抗向量与同年龄段的欧洲儿童不同。
鉴于不同地理区域之间存在相当大的种族多样性，我们的结果证实了为每个国家定义全身阻抗向量参考值的重要性。
