18～49岁成年人BCAⅠ与DEXA两法身体成分测定结果的比对研究

Comparison of Body Composition by Bioelectrical Impedance( BCAⅠ)and Dual-Energy X-Ray Absorptiometry in 18～49-years-old Adult

通过对18~49岁成年人生物电阻抗法（BCAⅠ）与双能X线吸收测定法（DEXA）的身体成分测定结果进行比对研究,为BCAⅠ体成仪的实践应用提供参考依据。方法 采用BCAⅠ与DEXA两法分析了132名成年人的身体成分,其中,男65名,女67名,年龄为（30.20±8.94）岁,BMI为（22.47±4.00）kg/m2,获取瘦体重（LBM）、肌肉重（SMM）、骨矿含量（BMC）、脂肪量（FM）、脂肪率（FM%）、躯干脂肪量（TFM）等,应用Bland-Altman一致图谱法与简单线性回归法比对了两测量结果间的一致性。结果 LBM、SMM、BMC、FM、FM%、TFM等指标两测量结果间具有较高的相关性（0.712~0.953,P〈0.01）,男女LBM、SMM、BMC参数BCAⅠ的测量结果高于DEXA（P〈0.01）,但FM、FM%、TFM参数BCAⅠ的测量结果低于DEXA（P〈0.01）。与DEXA法相比,BCAⅠ法趋向于低估肥胖成年人与高估消瘦成年人的FM、TFM与FM%。结论 采用BCAⅠ体成仪分析18~49岁成年人的体成分时,与体脂正常者相比,肥胖与消瘦成年人体成分测量结果的准确性降低。

Objective To compare body compositions determined by Bioelectrical Impedance （BCA I ） and Dual -Energy X -Ray Absorptiometry （DEXA） in 18 - 49 -years -old adult, and provide a reference for the practical application of BCA I . Methods Lean body mass（ LBM）, skeletal muscle mass（ SMM）, bone mineral content（BMC）, fat mass（FM）, percent FM （ FM% ）, trunk FM （TFM） of 132 adults,65 males, 67females, age （30.20 ± 8.94） years, BMI （ 22.47 ±4.00） kg/m2, who were estimated by a segmental multi -frequency bioelectrical impedance analysis device （BCA I ）, and compared to body composition measured by DEXA. Bland -Altman analyses and simple linear regression analyses were used to determine the agreement between two methods. Results The result estimated by BCA I correlates with DEXA for LBM, SMM, BMC, FM, FM%, and TFM were generally good （0.712 -0.953,P〈0.01）. LBM, SMM, BMC recorded by BCA I were greater than by DEXA both in males and females （P 〈0.01 ）. However, FM, FM%, TFM recorded by BCA I were lower than by DEXA （P 〈 0.01 ）. Compared with the DEXA method, the BCA I tended to underestimate FM, TFM, and FM% in fatter adults and to overestimate FM, TFM, and FM% in leaner adults. Conclusion The body composition in 18 - 49 year old a- dult estimated by BCA I are not interchangeable with those from DEXA, compared with normal - weight subjects, they are less accurate in fatter and leaner adults.