生物电阻抗法测量3~6岁儿童体成分的准确性

Validation of bioelectrical impedance analysis in measuring body composition of children aged from 3 to 6

目的评价生物电阻抗法(BIA)和双能X线吸收法(DXA)测量3~6岁中国儿童体成分的一致性。方法2017年11月16日至12月8日选取来自天津市津南区某幼儿园3~6岁儿童230例,分别使用BIA及DXA测量其全身肌肉量(SLM)及脂肪量(BFM),并根据性别、年龄、体质量指数(BMI)进行分组,分析各组儿童体成分测量结果的一致性。结果BIA测量的SLM及BFM与DXA具有显著相关性(R2=0.951、0.947,均P<0.001)。Bland-Altman结果中,BIA测量的SLM高于DXA 0.70 kg(95%CI:-1.78~0.38),BFM低于DXA 1.36 kg(95%CI:0.19~2.52)。在不同性别、年龄及BMI儿童中也存在相同的趋势,BIA测量的男、女童的SLM均高于DXA,男童相差0.57 kg(95%CI:-1.63~0.49),女童相差0.84 kg(95%CI:-1.88~0.20)。BFM测量结果BIA均低于DXA,男童相差1.23 kg(95%CI:0.11~2.36),女童相差1.49 kg(95%CI:0.34~2.64);各年龄组BIA测量的SLM均高于DXA,3岁组相差0.67 kg(95%CI:-1.74~0.41),4岁组相差0.76 kg(95%CI:-1.65~0.13),5岁组相差0.69 kg(95%CI:-1.85~0.47),6岁组相差0.67 kg(95%CI:-1.75~0.41)。BFM测量结果BIA均低于DXA,3岁组相差1.09 kg(95%CI:-0.12~2.30),4岁组相差1.44 kg(95%CI:0.60~2.28),5岁组相差1.39 kg(95%CI:0.15~2.64),6岁组相差1.43 kg(95%CI:0.38~2.48)但在肥胖儿童中,BIA与DXA的差异最小,SLM相差0.39 kg,BFM相差0.93 kg。结论BIA测量3~6岁儿童SLM及BFM与DXA具有较高的一致性。

Objective To examine the concordance between bioelectrical impedance analysis(BIA)and dual energy X-ray absorptiometry(DXA)in determining body composition of children aged between 3 and 6.Methods A total of 230 children aged 3-6 from a kindergarten in Jinnan,Tianjin were enrolled in this study from November 16th to December 8th,2017.The soft lean mass(SLM)and the body fat mass(BFM)of the children were measured by using BIA and DXA.The children were divided into several groups by sex,age and body mass index(BMI).The consistency of the body composition results between BIA and DXA in each group was analyzed.Results The SLM and BFM assessed by BIA were significantly correlated with those measured by DXA(R2=0.951,0.947,all P<0.001).The Bland-Altman plots suggested that the SLM measured by BIA was 0.70 kg(95%CI:-1.78-0.38)higher in that by DXA,and the BFM measured by BIA was 1.36 kg(95%CI:0.19-2.52)lower in that by DXA.A similar trend could be seen in children stratified by age,sex and BMI.The SLM of boys and girls measured by BIA was 0.57 kg(95%CI:-1.63-0.49)and 0.84 kg(95%CI:-1.88-0.20)higher than those by DXA,respectively.The BFM of boys and girls measured by BIA was 1.23 kg(95%CI:0.11-2.36)and 1.49 kg(95%CI:0.34-2.64)lower than that by DXA,respectively.The SLM measured by BIA was 0.67 kg(95%CI:-1.74-0.41),0.76 kg(95%CI:-1.65-0.13),0.69 kg(95%CI:-1.85-0.47)and 0.67 kg(95%CI:-1.75-0.41)higher than those by DXA in the 3 to 6-year-old groups,respectively.The BFM measured BIA was 1.09 kg(95%CI:-0.12-2.30),1.44 kg(95%CI:0.60-2.28),1.39 kg(95%CI:0.15-2.64)and 1.43 kg(95%CI:0.38-2.48)lower than that by DXA in the 3 to 6-year-old groups,respectively.Moreover,the smallest difference of the SLM and BFM were observed between BIA and DXA in the obese child.The SLM deviation between BIA and DXA was estimated within±0.39 kg and the BFM deviation was within±0.93 kg.Conclusions There is high consistency between BIA and DXA in the assessment of the SLM and BFM of children aged from 3 to 6.