多频生物电阻抗法与双能X线吸收法测量成年超重、肥胖人群全身肌肉含量的一致性分析

Comparison whole-body muscle mass assessed by dual-energy X-ray absorptiometry and multi-frequency bioelectrical impedance in overweight and obese adults

目的 分析双能X线吸收法（DXA）和多频生物电阻抗法（MF-BIA）测量成年超重与肥胖人群全身肌肉含量的一致性,建立MF-BIA校正预测模型.方法 于2014年4月1日至5月2日期间,以志愿招募的形式,选取在北京居住满1年、22-55岁、自报BMI≥24 kg/m^2的志愿者1488名,排除体检时BMI≤24 kg/m^2或存在器质性疾病的171名志愿者后,共纳入1317名研究对象.采用MF-BIA和DXA同时测定其全身肌肉含量,采用配对t检验比较MF-BIA与DXA测量超重、肥胖者全身肌肉含量的差异;组内相关系数和Bland-Altman图分析2种方法测量结果 的一致性;并采用线性回归建立MF-BIA的校正预测模型.结果MF-BIA测量成年超重男性、肥胖男性、超重女性、肥胖女性的全身肌肉含量与DXA测量结果的差值分别为（3.29±1.94）、（2.05±2.65）、（0.17±1.85）和（-2.22±2.89）kg,除超重女性外,差异均有统计学意义（P值均〈0.05）.成年超重男性、肥胖男性、超重女性、肥胖女性人群中两种方法所测结果的组内相关系数分别为0.958、0.956、0.911、0.851,且均有统计学意义（P值均〈0.001）;Bland-Altman图显示,MF-BIA和DXA测量超重男性、肥胖男性、超重女性、肥胖女性全身肌肉含量的一致性限分别为-0.51-7.09、-3.14-7.24、-3.46-3.80、-7.88-3.44 kg.MF-BIA校正预测模型为：超重男性人群：yDXA=-0.648＋0.952xMF-BIA,肥胖男性人群：yDXA=-3.646＋1.026xMF-BIA,超重女性人群：yDXA=-4.800＋1.117xMF-BIA,肥胖女性人群：yDXA=-9.884＋1.287xMF-BIA.结论 MF-BIA和DXA测量我国成年超重、肥胖男性和肥胖女性人群全身肌肉含量的一致性较差;在我国成年超重、肥胖男性和肥胖女性人群中,使用MF-BIA测量全身肌肉含量时需进行校正.

Objective To investigate consistency of whole-body muscle mass （WBMM） assessed using multi-frequency bioelectrical impedance analysis （MF-BIA） and dual energy X-ray Absorptiometry （DXA） measurement, and to delvelop the correction regression formulas for the method of MF-BIA. Methods 1488 participants who resided in Beijing longer than one year, under 22 to 55 years of age, with self-report BMI≥24 kg/m^2 were voluntarily recruited based on convenience sampling in Beijing, from April 1st 2014 to May 2nd 2014. After excluded 171 participants who BMI≤24 kg/m^2 or with organic diseases when physical examination, Finally 1317 overweight/obese participants were enrolled into the current study. All the subjects received the measurement of WBMM using both MF-BIA and DXA methods. The paired-samples T test was used to compare the difference of measurement values between MF-BIA and DXA methods. We evaluated the agreement of WBMM measured by MF-BIA and DXA using the interclass correlation coefficients （ICC） and the Bland-Altman plots, and using linear regression method established correction regression formulas. Results The differences of overweight male, obese male, overweight female, and obese female were （3.29 ± 1.94）, （2.05 ± 2.65）, （0.17 ± 1.85）, and （-2.22 ± 2.89） kg between methods of MF-BIA and DXA, respectively; Except the overweight female, the others groups had the statistically significant difference （P〈0.05）. The ICC for overweight male, obese male, overweight female, and obese female were 0.958, 0.956, 0.911, and 0.851, respectively （P〈0.001）. Bland-Altman plots showed that the limit of agreement for four groups were-0.51-7.09,-3.14-7.24,-3.46-3.80, and-7.88-3.44 kg, respectively. Correction regression formulas： overweight male population： yDXA=-0.648＋0.952 xMF-BIA; obese male population： yDXA=-3.646＋1.026xMF-BIA; overweight female groups： yDXA=-4.800＋1.117 xMF-BIA; obese female group： yDXA=-9.884＋1.287xMF-BIA. Conclusion The correlation and agreement of WBMM measured by the methods of BIA and DXA were relative weak in Chinese excess weight male and obese female adults. Therefore, measuring WBMM by MF-BIA method in these adults should be corrected to reduce bias compared with the DXA method.