生物电阻抗法与双能X线吸收法测量超重/肥胖合并多囊卵巢综合征病人体成分的对比研究

Comparison between bioelectrical impedance analysis and dual energy x-ray absorptiometry in overweight/obese polycystic ovary syndrome's body composition measurements

目的:分析多频生物电阻抗法(MF-BIA)和双能X线吸收法(DXA)测量超重/肥胖合并多囊卵巢综合征病人人体成分各指标之间的差异。方法:采用前瞻性研究方法,招募超重/肥胖合并多囊卵巢综合征病人63人,分别采用MF-BIA法和DXA法测定受试者的脂肪含量(FM)、体脂率(%BF)、去脂体质量(FFM)、骨矿物质含量(BMC),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,采用Bland-Altman图和组内相关系数ICC分析评价方法间的一致性,并采用线性回归建立MF-BIA的校正预测模型。结果:DXA法测得超重/肥胖合并多囊卵巢综合征病人脂肪含量和体脂率高于MF-BIA法,差异有统计学意义(P<0.001),MF-BIA测得去脂体质量及骨矿物质含量高于DXA法,差异具有统计学意义(P<0.001)。MFBIA和DXA测量的脂肪含量和去脂体质量呈中等相关,体脂率和骨矿物质含量呈弱相关。两种方法所测脂肪含量、体脂率、去脂体质量及骨矿物质含量结果的ICC为0.76、0.30、0.79、0.39,差异均具有统计学差异(P<0.001)。Bland-Altman图显示,MF-BIA和DXA测量脂肪含量、体脂率、去脂体质量及骨矿物质含量的一致性限分别为-11.61~7.16,-14.33~6.60,-3.84~10.99,-0.59~1.12。超重/肥胖合并多囊卵巢综合征病人脂肪含量、体脂率、去脂体质量及骨矿物质含量的回归模型分别为:yDXA=13.55+0.63×MF-BIA;yDXA=34.86+0.21×MF-BIA;yDXA=7.57+0.76×MF-BIA;y DXA=1.52+0.38×MF-BIA。结论:MF-BIA和DXA测量结果具有一定的相关性,但一致性欠佳。在超重/肥胖合并多囊卵巢综合征病人中,使用MF-BIA法测量脂肪含量、体脂率、去脂体质量、骨矿含量需进行校正。

Objective:To analyze the difference of body composition indexes measured by multi-frequency bioelectrical impedance(MF-BIA)and dual-energy X-ray absorptiometry(DXA)in overweight/obese patients with polycystic ovary syndrome.Methods:Sixty-three overweight/obese patients with polycystic ovary syndrome were recruited,and their fat mass(FM),percent body fat(%BF),fat-free mass(FFM)and bone mineral content(BMC)were measured by MF-BIA method and DXA method respectively.The correlation between the two methods was evaluated by Pearson product moment coefficient,and the mean difference between the two methods was compared by paired t-test.The consistency between the evaluation methods was analyzed by using the Bland-Altman diagram and ICC,and the MFBIA correction prediction model was established by linear regression.Results:FM and%BF measured by DXA method were significantly higher than those measured by MF-BIA method(P<0.001).The FFM and BMC measured by MF-BIA method were significantly higher than those measured by DXA method(P<0.001).The FM and FFM measured by MF-BIA and DXA were moderately correlated,while the%BF and BMC were weakly correlated.The ICC of FM,%BF,FFM and BMC measured by the two methods were 0.76,0.30,0.79,and 0.39.The ICC for four groups between MF-BIA and DXA measurement were statistically significant in all subgroups(P<0.001).Bland-Altman plots showed that the limit of agreement for four groups were-11.61~7.16,-14.33~6.60,-3.84~10.99,-0.59~1.12,respectively.The regression models of four group in overweight/obese patients with polycystic ovary syndrome were:yDXA=13.55+0.63×MF-BIA;yDXA=34.86+0.21×MF-BIA;yDXA=7.57+0.76×MF-BIA;yDXA=1.52+0.38×MF-BIA.Conclusion:There is a certain correlation between the measurement results of MF-BIA and DXA,but the consistency is unsatisfying.In overweight/obese patients with polycystic ovary syndrome,the measurement of fat content,body fat rate,fat-free body weight and bone mineral content by MF-BIA method needs to be corrected.