生物电阻抗法与双能X线吸收法测量成人体成分指标的比较研究

COMPARISON OF BIOELECTRICAL IMPEDANCE ANALYSIS AND DUAL ENERGY X-RAY ABSORPTIOMETRY IN MEASUREMENT OF BODY COMPOSITION IN CHINESE ADULTS

目的比较生物电阻抗法(bioelectrical impedance analysis,BIA)和双能X线吸收法(dual energy X-ray absorptiometry,DXA)测量成人体成分各指标之间的差异。方法招募18~65岁成年受试者共计386名,同时采用BIA和DXA测量受试者的总体脂率、躯干体脂率、体脂含量和去脂体重。利用Pearson积矩相关系数评价两种方法测量结果的相关性,用配对t检验比较两种方法测量均值差异,用均方根误差(root mean squared error,RMSE)和最小乘积回归(ordinary least product regression,OLP)来评价两种方法测量结果的一致性。结果BIA与DXA测量的男性和女性体成分指标的相关系数均在0.75以上(P<0.001)。BIA测量的男性总体脂率、躯干体脂率和体脂含量的结果均值分别低于DXA测量结果均值。BIA测量的男性和女性去脂体重结果均值显著高于DXA测量结果的均值(P<0.001)。男性和女性各测量指标RMSE均较小,各指标均存在固定偏差和比例偏差。结论BIA和DXA测量结果的相关性较好,但一致性欠佳。

Objective To compare bioelectrical impedance analysis(BIA)with dual energy X-ray absorptiometry(DXA)in the measurement of body composition of Chinese adults.Methods A total of 386 adults aged 18 to 65 were recruited.BIA and DXA were used to measure the total fat percentage,trunk fat percentage,fat mass and fat free mass.The Pearson product moment coefficient and paired t-test were used to study the correlations and differences between BIA and DXA.The root mean squared error(RMSE)and ordinary least product regression(OLP)were used to determine the consistency between the two methods.Results The correlation coefficients for all the measurements of body composition were above 0.75(P<0.001)for both male and female subjects.The mean values of total fat percentage,trunk fat percentage and fat mass measured by BIA were lower than those measured by DXA in men.However,the mean value of fat free mass measured by BIA was higher than that measured by DXA(P<0.001)in both genders.The RMSE of all the four indexes of body composition was small.There were fixed bias and proportional bias between the two methods.Conclusion The measurements by BIA and DXA are highly correlated,but somewhat inconsistent.