INSERM U669, PSIGIAM 'Paris Sud Innovation Group in Adolescent Mental Health', Maison des Adolescents, 97 Boulevard De Port Royal, 75014 Paris, France.
Clin Nutr. 2011 Dec;30(6):746-52. doi: 10.1016/j.clnu.2011.05.012. Epub 2011 Jul 29.
BACKGROUND & AIMS: Body weight changes do not reflect the respective changes of body compartments, namely fat-free mass (FFM) and fat mass (FM). Both bioelectrical Impedance Analysis (BIA) and the Dual X-ray absorptiometry (DXA) measure FFM and FM. This study in underweight patients with anorexia nervosa (AN) aims to compare measurements of FM and FFM done by DXA and BIA using 5 different BIA equations already validated in healthy population and to identify the most suitable BIA equation for AN patients.
Fifty female patients with AN (BMI=14.3 ± 1.49, age=19.98 ± 5.68yrs) were included in the study. Body composition was measured by DXA (Delphi W, Hologic, Bedford, MA) and by 50 kHz BIA (FORANA, Helios) using 5 different BIA equations validated in healthy population (Sun, Geneva, Kushner, Deurenberg and Roubenoff equations). Comparison between the DXA and the 5 BIA equations was done using the sum of the squares of differences and Bland-Altman plots.
The Deurenberg equation gave the best estimates of FFM when compared to the measurements by DXA (FFM(dxa)=35.80 kg versus FFM(deurenberg)=36.36 kg) and very close estimates of FM (FM(dxa)=9.16 kg and FM(deurenberg)=9.57 kg) The Kushner equation showed slightly better estimates for FM (FM(kushner)=9. 0kg) when compared to the DXA, but not for FFM. Sun equation gave the broadest differences for FM and FFM when compared with DXA.
The best available BIA equation to calculate the FFM and the FM in patients with AN is the Deurenberg equation. It takes into account the weight, height and age and is applicable in adults and adolescents AN patients with BMI of 12.8-21.0, and for ages between 13.4 and up to 36.9 years.
体重变化并不能反映身体各部位（即去脂体重（FFM）和脂肪量（FM））的相应变化。生物电阻抗分析（BIA）和双能 X 射线吸收法（DXA）均测量 FFM 和 FM。本研究旨在比较已在健康人群中验证的 5 种不同 BIA 方程对 DXA 测量的 FM 和 FFM 的测量值，并识别最适合 AN 患者的 BIA 方程。
本研究纳入了 50 名 AN 女性患者（BMI=14.3±1.49，年龄=19.98±5.68 岁）。使用 5 种不同的已在健康人群中验证的 BIA 方程（Sun、Geneva、Kushner、Deurenberg 和 Roubenoff 方程）通过 DXA（Delphi W，Hologic，Bedford，MA）和 50 kHz BIA（FORANA，Helios）测量身体成分。通过平方和差异和 Bland-Altman 图比较 DXA 和 5 种 BIA 方程。
与 DXA 测量值相比，Deurenberg 方程对 FFM 的估计最佳（FFM(dxa)=35.80kg 与 FFM(deurenberg)=36.36kg），对 FM 的估计非常接近（FM(dxa)=9.16kg 和 FM(deurenberg)=9.57kg）。与 DXA 相比，Kushner 方程对 FM 的估计略好（FM(kushner)=9.0kg），但对 FFM 则不然。Sun 方程与 DXA 相比，FM 和 FFM 的差异最大。
在 AN 患者中计算 FFM 和 FM 的最佳 BIA 方程是 Deurenberg 方程。它考虑了体重、身高和年龄，适用于 BMI 为 12.8-21.0 的成年和青少年 AN 患者，以及年龄在 13.4 岁至 36.9 岁之间的患者。
