体质量指数和胸部CT特征在综合评估慢性阻塞性肺疾病中的价值

目的 依据营养状况和胸部CT影像表现,分析慢性阻塞性肺疾病(COPD)患者的临床特征,探讨其在综合评估COPD中的应用价值。方法 纳入2017年6月至2018年6月在北京协和医院和民航总医院呼吸科就诊的256例COPD稳定期患者,收集人口学资料、身高、体质量、吸烟史、急性加重次数,完善肺功能检查及COPD评估测试(CAT)问卷,分析Goddard评分与肺功能、CAT评分、急性加重次数间的关系,并探索不同体质量指数(BMI)分级和各CT表现型COPD患者的临床特征。结果 体质量正常(t=-2.701,P=0.0080)、超重(t=-3.506,P=0.001)和肥胖组(t=-4.323,P=0.000)的第1秒用力呼气容积占预计值百分比(FEV₁%pred)明显高于体质量过低组,肥胖组明显高于体质量正常组(t=-3.096,P=0.002)。体质量正常(t=-3.081,P=0.002)和超重组(t=-2.766,P=0.006)的用力肺活量占预计值的百分比(FVC%pred)明显高于体质量过低组。超重组的第1秒用力呼气容积(FEV₁)/用力肺活量(FVC)明显高于体质量正常组(t=-3.702,P=0.001),肥胖组明显高于体质量过低组(t =-4.742,P=0.000)、体质量正常组(t=-5.785,P=0.000)和超重组(t=-2.984,P=0.003)。超重组的一氧化碳弥散量占预计值的百分比(DLco%pred)明显高于体质量过低组(t=-3.042,P=0.003)和体质量正常组(t=-3.128,P=0.002),肥胖组也明显高于体质量过低组(t=-4.742,P=0.000)和体质量正常组(t=-5.785,P=0.000)。超重(Z=4.535,P=0.000)和肥胖组(Z=5.422,P=0.000)的Goddard评分明显低于体质量正常组。偏相关分析结果显示,Goddard 评分与FEV₁/FVC(r=-0.230,P=0.022)和DLco%pred(r=-0.531,P=0.000)呈显著负相关,与CAT评分(r =0.244,P=0.021)呈显著正相关。E型(t=3.467,P=0.001)和M型(t=3.031,P=0.003)的BMI、E型(t=2.484,P=0.015)和M型(t=2.969,P=0.004)的FEV₁/FVC及E型(t=4.928,P=0.000)和M型(t=2.489,P= 0.0163)的DLco%pred均明显低于A型;M型的FEV₁%pred、FVC%pred、残气量/肺总量和急性加重方面均较A、E两型更差,但差异无统计学意义(P均>0.05)。结论 COPD患者的营养水平与肺功能、肺气肿程度、急性加重次数密切相关。胸部CT严重程度和表型评估可以为COPD分型和治疗提供有效的参考依据。

Values of Body Mass Index and Chest CT Features in the Assessment of Chronic Obstructive Pulmonary Disease

Objective To investigate the clinical values of nutritional status and chest CT phenotypes in the assessment of chronic obstructive pulmonary disease(COPD). Methods A total of 256 patients with stable COPD were enrolled from Peking Union Medical College Hospital and Civil Aviation General Hospital from June 2017 to June 2018.Demographic data,height,weight,smoking history,and number of exacerbations were collected.Pulmonary function tests and COPD assessment test(CAT)questionnaire-based survey were performed.The correlations of Goddard score with pulmonary function,CAT score,and number of exacerbations were analyzed.The clinical features of COPD patients with different body mass index(BMI)grades and CT phenotype were analyzed. Results The forced expiratory volume in one second as percentage of predicted value(FEV₁%pred)was significantly higher in normal body mass group(t=-2.701,P=0.0080),overweight group(t=-3.506,P=0.001),and obese group(t=-4.323,P=0.000)than in low body mass group and was significantly higher in obese group than in normal body mass group(t=-3.096,P=0.002).The forced vital capacity as percentage of predicted value(FVC%pred)of normal body mass group(t=-3.081,P=0.002)and overweight group(t=-2.766,P=0.006)were significantly higher than that of low body mass group.The forced expiratory volume in one second(FEV₁)/forced vital capacity(FVC)was significantly higher in overweight group than in normal body mass group(t=-3.702,P=0.001)and significantly higher in obese group than in low body mass group(t=-4.742,P=0.000),normal body mass group(t=-5.785,P=0.000),and overweight group(t=-2.984,P=0.003).In addition,the carbon monoxide diffusing capacity as percentage of predicted value(DLco%pred)was significantly higher in overweight group than in underweight(t=-3.042,P=0.003)and normal body mass groups(t=-3.128,P=0.002)and significantly higher in obese group than in underweight group(t=-4.742,P=0.000)and normal body mass group(t=-5.785,P=0.000).The Goddard scores of overweight(Z=4.535,P=0.000)and obese groups(Z=5.422,P=0.000)were significantly lower than that of normal body mass group.Partial correlation analysis showed that Goddard score was negatively correlated with FEV₁/FVC(r =-0.230,P = 0.022)and DLco%pred(r =-0.531,P = 0.000)and positively correlated with CAT score(r = 0.244,P = 0.021).BMI of phenotype E(t=3.467,P=0.001)and M(t=3.031,P=0.003),FEV₁/FVC of phenotype E(t=2.484,P=0.015)and M(t=2.969,P=0.004)as well as DLco%pred of phenotype E(t=4.928,P=0.000)and M(t=2.489,P=0.0163)were significantly lower than those of phenotype A.Patients with phenotype M had worse FEV₁%pred,FVC%pred,residual volume/total lung capacity and number of acute exacerbations than patients with phenotypes A and E,but the differences were not statistically significant(all P >0.05). Conclusions The nutritional status is closely related to lung function,severity of emphysema,and number of exacerbations in COPD patients.Chest CT phenotype is clinically valuable in the assessment of COPD.