脊髓性肌萎缩症患者肺功能分析

Lung function of patients with spinal muscular atrophy

目的:分析脊髓性肌萎缩症(SMA)患者的肺功能特点,为SMA多学科管理提供依据。方法:以2019年7月至2021年3月在浙江大学医学院附属儿童医院SMA多学科门诊就诊的30例SMA患者为研究对象,其中Ⅰ型1例、Ⅱ型18例、Ⅲ型11例;男17例,女13例;年龄4岁~21岁10个月。回顾性分析不同临床分型SMA患者的临床特征、脊柱影像学检查结果及肺功能特点,探讨SMA患者肺功能损害的可能影响因素。肺功能以用力呼气流量-容积曲线测定,测定用力肺活量(FVC)、第1秒用力呼气容积(FEV 1)、1秒率(FEV 1/FVC)、呼气峰值流量(PEF),结果以实测值占预计值的百分比表示。测量Cobb角以评价脊柱侧弯。采用Pearson相关性分析及多元线性回归分析评估Ⅱ型SMA患者肺功能与年龄及Cobb角的关系。采用Pearson相关性分析及一元线性回归分析评估Ⅱ型SMA患者Cobb角与年龄的关系。结果:1例Ⅰ型患者肺功能显示FVC、FEV 1下降;18例Ⅱ型患者中14例存在肺功能异常(77.8%):12例FVC不同程度下降(66.7%)、10例FEV 1不同程度下降(55.6%)、12例PEF不同程度下降(66.7%);11例Ⅲ型SMA患者中,1例出现FVC下降(9.1%)。Ⅱ型与Ⅲ型SMA患者的肺功能比较显示,Ⅱ型SMA患者FVC、FEV 1、PEF显著低于Ⅲ型SMA患者[(62.4±31.8)%比(90.8±11.0)%,(66.3±33.3)%比(97.8±9.9)%,(65.3±30.1)%比(98.6±21.1)%,均P<0.01]。Pearson相关性分析显示,Ⅱ型SMA患者FVC与年龄、Cobb角相关(r=-0.864、-0.865,均P<0.001),FEV 1与年龄、Cobb角相关(r=-0.878、-0.863,均P<0.001),PEF与年龄、Cobb角相关(r=-0.831、-0.783,均P<0.001),Cobb角与年龄相关(r=0.922,P<0.001)。多元线性回归分析显示,Ⅱ型SMA患者FVC与Cobb角呈线性相关(R2=0.748,P<0.001),FEV 1与年龄呈线性相关(R2=0.770,P<0.001),PEF与年龄呈线性相关(R2=0.690,P<0.001)。一元线性回归分析显示,Cobb角与年龄呈线性相关(R2=0.851,P<0.001)。结论:SMA患者肺功能损害可出现FVC、FEV 1、PEF下降。不同分型SMA患者肺功能损害程度不同。随着年龄增长,Ⅱ型SMA患者Cobb角增加,FVC、FEV 1、PEF下降。了解SMA患者肺功能损害的影响因素有助于对其开展多学科个体化管理。

Objective To analyze the characteristics of lung function in patients with spinal muscular atrophy(SMA)to provide evidence for multidisciplinary management of SMA.Methods A total of 30 patients with SMA treated in the SMA multidisciplinary clinic of the Children′s Hospital,Zhejiang University School of Medicine from July 2019 to March 2021 were enrolled,including 1 child with type I,18 patients with typeⅡand 11 children with typeⅢ.There were 17 males and 13 females;the age ranged from 4 years to 21 years and 10 months old.A retrospective study was conducted to analyze the clinical features,spinal imaging findings and lung functions of patients with different clinical types of SMA and explore the factors influencing the lung functions of patients with SMA.Pulmonary function was measured by forced expiratory flow-volume curve.Forced vital capacity(FVC),forced expiratory volume in one second(FEV1),FEV1/FVC and peak expiratory flow(PEF)were measured.The results were expressed as the percentage of the measured value to predicted value.The Cobb angle was measured to evaluate scoliosis.Pearson correlation analysis and multiple linear regression analysis were used to evaluate the relationship between lung function and age and Cobb angle in patients with typeⅡSMA.Pearson correlation analysis and univariate linear regression analysis were used to evaluate the relationship between Cobb angle and age in patients with typeⅡSMA.Results Pulmonary function in 1 type I patient showed decreased FVC and FEV1;Among 18 patients with typeⅡ,14 cases had abnormal lung function(77.8%):FVC decreased in 12 patients(66.7%),FEV1 decreased in 10 patients(55.6%),PEF decreased in 12 patients(66.7%).Among 11 patients with typeⅢ,one had decreased FVC(9.1%).FVC,FEV1 and PEF of patients with typeⅡwere significantly lower than those of patients with typeⅢ[(62.4±31.8)%vs.(90.8±11.0)%,(66.3±33.3)%vs.(97.8±9.9)%,(65.3±30.1)%vs.(98.6±21.1)%,all P<0.01].Pearson correlation analysis showed that FVC of patients with typeⅡSMA was correlated with age and Cobb angle(r=-0.864,-0.865,all P<0.001),FEV1 was correlated with age and Cobb angle(r=-0.878,-0.863,all P<0.001),PEF was correlated with age and Cobb angle(r=-0.831,-0.783,all P<0.001),and Cobb angle was related to age(r=0.922,P<0.001).Multiple linear regression analysis indicated that FVC of patients with typeⅡSMA was linearly correlated with Cobb angle(R2=0.748,P<0.001),FEV1 was linearly correlated with age(R2=0.770,P<0.001),PEF was linearly related to age(R2=0.690,P<0.001).Univariate linear regression analysis revealed that Cobb angle of patients with typeⅡSMA was linearly related to age(R2=0.851,P<0.001).Conclusions FVC,FEV1 and PEF may decrease in patients with SMA.The degree of lung function damage is different in different types of SMA patients.With the increase of age,Cobb angle increases and FVC,FEV1 and PEF decrease in patients with typeⅡSMA.Understanding the factors influencing the pulmonary function damage in patients with SMA is conductive to carrying out individual multidisciplinary management.