应用核磁共振测定儿童内脏脂肪验证生物电阻抗技术准确性的研究

Using magnetic resonance imaging to validate bioelectrical impedance analysis for measuring the area of visceral adipose tissue

目的验证生物电阻抗技术（BIA）在儿童内脏脂肪测定的准确性。方法招募7-18岁受试者，根据报名顺序和入组标准进行筛选。受试者入组后7d内完成BIA和核磁共振（MRI）检测。BIA检测和腹部MRI扫描均在清晨空腹状态下完成。MRI脐平面图像分析得到内脏脂肪面积，BIA测试后直接获得内脏脂肪面积数据。以MRI作为标准方法，将两者测定结果进行比对，并建立简单线性方程。结果纳入60例受试者，男女各30例，年龄（11.9±4.6）岁，体质指数为（22.8±7.3）kg/m2。BIA测定内脏脂肪面积为（85.4±64.2）cm2，高于MRI测定结果（49.4±32.4）cm2（t=-6.524，P=0.000）。Pearson相关系数r=0.806（P=0.000）。建立线性校正方程：y=0.41x＋14.78，β值（95%CI）为0.41（0.04-0.81）。绘制Bland-Altman图：±1.96s为（35.9±83.7）cm2。结论BIA测定内脏脂肪面积结果稳定，相关性好，可以用于快速评价儿童的内脏脂肪情况。

ObjectiveTo validate bioelectrical impedance analysis（BIA） for measuring the area of visceral fat of school-age populations using MRI as a reference method.MethodsSixty healthy children （30 boys and 30 girls） aged 7 to 18 years were enrolled in the study. Both MRI and BIA were completed in seven days. We obtained the indexes of the body composition from BIA and MRI in the morning before the participants had their breakfast. For reference, the navel plane image obtained with MRI was used to analyze the area of adipose tissue. With BIA, the area of visceral adipose tissue could be derived directly.ResultsSixty healthy school-age children were enrolled in the study. The average age of the school children was （11.9±4.6） years, and their BMI was （22.8±7.3） kg/m2. The average area of visceral fat obtained with BIA was （85.4±64.2） cm2, which was higher than that obtained with MRI [（49.4±32.4） cm2]（t=-6.524, P=0.000）. The Pearson correlation coefficient was r=0.806 （P=0.000） and the simple linear regression equation for the area between the two was： y= 0.41x＋ 14.78; β （95%CI） was 0.41（0.04-0.81）. The Bland-Altman plot was ±1.96 s： （35.9±83.7） cm2.ConclusionBIA is comparable to MRI for assessing the area of visceral fat and is a reliable and simple tool to evaluate the visceral fat area in school-age children.