不同诊断标准下相位角对老年男性肌少症的诊断价值分析

Diagnostic value of phase angle for sarcopenia in older men under different diagnostic criteria

背景目前肌少症的诊断标准尚未达成明确共识。利用生物电阻抗分析(bioelectrical impedance analysis,BIA)获得相位角可以在一定程度上反映机体功能,预测肌少症的发生风险。目的探究BIA测得的相位角在不同诊断标准中对老年男性肌少症的诊断价值及意义。方法 2019年4-7月在北京市多个社区招募≥60岁的老年男性1 009例,通过BIA法检测50 kHz相位角和其他肌肉功能相关参数。分别使用亚洲肌少症工作组、欧洲肌少症工作组、国际肌少症工作组、美国国立卫生研究院基金会等制订和更新的6种肌少症诊断标准对其进行诊断。通过Spearman相关及多元线性回归分析相位角与各肌少症诊断要素的相关性,单因素及多因素logistic回归研究相位角与肌少症的关联性,最后根据AUC面积评价相位角的诊断价值,计算约登指数,确定最佳截断值。结果 1 009名老年男性相位角平均值为4.89°±0.70°。根据6种标准诊断肌少症的患病率为2.3%-12.2%。随着年龄的增加,相位角降低,肌少症的患病率逐渐升高。在相关性分析中相位角与肌少症的诊断要素均相关(P均<0.05)。多元线性回归显示相位角与年龄、骨骼肌质量指数(skeletal muscle mass index,SMI)、握力、步速和简易体能状况量表评分(short physical performance battery,SPPB)呈线性相关(P<0.05,R2=0.563)。多因素logistics回归分析发现在所有诊断标准中,年龄(OR>1)、相位角(OR<1)均与肌少症独立关联。通过约登指数计算不同标准下相位角诊断肌少症的截断值为4.15°-4.55°。结论相位角与年龄、肌力、肌量、身体功能呈中度相关。在所有诊断标准中,高龄、低相位角均与肌少症相关。相位角易于测量,可对无法进行功能测试的老年人进行肌少症的早期预测及诊断。

Background At present,there is no clear consensus on the diagnostic criteria of sarcopenia.Using bioelectrical impedance analysis(BIA)to obtain the phase Angle(PhA)can reflect the body function to a certain extent and predict the risk of sarcopenia.Objective To explore the diagnostic value and significance of PhA measured by BIA in different diagnostic criteria for sarcopenia.Methods A total of 1009 eligible older men over 60 years old from several communities of Beijing were included.PhA at 50 kHz was measured by BIA and other parameters related to muscle function were recorded.Organizations such as the Asian sarcopenia working group,the European sarcopenia working group,the international sarcopenia working group,and the National Institutes of Health Foundation had developed and updated the diagnostic criteria for sarcopenia,so these criteria were used to diagnose sarcopenia.The correlations between PhA and the diagnostic components of sarcopenia were analyzed through spearman correlation analysis and multiple regression analysis.Univariate and multivariate logistics regression were used to illustrate the correlation between PhA and sarcopenia.Finally,the diagnostic value of the PhA was determined according to the AUC area,and the Youden index was calculated to determine the best cut-off value of the PhA.Results The mean PhA in 1009 older men was 4.38°±0.16°.The prevalence of sarcopenia ranged from 2.3%to 12.2%using the 6 criteria.With the increase of age,the value of PhA decreased,while the prevalence of sarcopenia gradually increased.In the correlation analysis,the PhA was significantly correlated with the components of diagnostic criteria to sarcopenia.Multiple linear regression showed that the PhA was linearly correlated with age,skeletal muscle mass index(SMI),grip strength,gait speed and short physical performance battery(SPPB)(P<0.05,R^(2)=0.563).Multivariate logistic regression analysis showed that among all diagnostic criteria,age(OR>1,P<0.05)and PhA(OR<1,P<0.05)were significantly associated with sarcopenia.The cut-off values of the PhA in predicting sarcopenia ranged from 4.15°to 4.55°.Conclusion PhA is moderately correlated with age,grip strength,SMI and body function.Moreover,in all diagnostic criteria,advanced age and low PhA are associated with sarcopenia.In general,the PhA is easy to measure,and can be used for early prediction and diagnosis of sarcopenia in the elderly who can not receive functional tests.