高分辨胸部CT定量分析对哮喘-慢阻肺重叠的应用研究

Application of quantitative analysis in asthma-COPD overlap through high-resolution chest CT

目的探讨慢性阻塞性肺病(COPD)、存在气流受限哮喘(Asthma FL+)及哮喘-慢阻肺重叠(ACO)患者高分辨胸部CT(HRCT)的特征差异及其鉴别诊断的价值。方法定量分析36例COPD、23例Asthma FL+、34例ACO患者高分辨胸部CT图像,测量气道参数及哥达德肺气肿指数(Goddard),比较其差异并与肺功能行相关性分析。结果 Asthma FL+组的第3级-5级WA%(3rdWA%-5thWA%)高于COPD组,差异有统计学意义(P=0.029、0.019、0.002);Asthma FL+组的第3级WA%(3rdWA%)、5级WA%(5thWA%)高于ACO组,差异有统计学意义(P=0.047、0.004);Asthma FL+组的第3级WT%(3rdWT%)、5级WT%(5thWT%)分别高于COPD组及ACO组,差异有统计学意义(P=0.041、0.032、0.009、0.040)。受试者工作特征曲线(ROC曲线)分析显示联合3thWT%+5thWA%能更好的鉴别气流受限哮喘与ACO (AUC=0.744,P=0.002,敏感度82.4%特异度60.9%)。COPD组哥达德肺气肿指数(Goddard)评分高于ACO组及Asthma FL+组,差异具有统计学意义(P<0.001),ROC曲线提示哥达德指数评分能更好的鉴别COPD与ACO(AUC=0.777,P<0.001,灵敏度97.2%特异度55.9%)。三组患者的5th(WA%、WT%)指标均与FEV1/FVC呈负相关,且相关性有统计学意义(P<0.05)。三组患者的Goddard评分与FEV1/FVC呈负相关,且ACO患者的Goddard评分与FEV1/FVC相关性有统计学意义(P=0.022)。结论 COPD、Asthma FL+、ACO三组患者高分辨胸部CT表现存在一定差异,ACO患者的近端气道参数与肺气肿指数与肺功能的相关性更显著且独特,3rd WT%联合5th WA%及肺气肿指数的自动定量测定有助于慢性阻塞性气道疾病亚型的鉴别,对于那些无法完成肺功能检测的患者评价其气流受限严重程度具有潜在的临床预测价值。

Objective To investigate the characteristic differences and differential diagnosis value of high-resolution CT(HRCT)in patients with chronic obstructive pulmonary disease(COPD),asthma with airflow restriction(asthma FL+)and asthma-COPD overlap(ACO).Methods Quantitative analysis was performed in 36 cases with COPD,23 cases with asthma FL+and 34 cases with ACO using HRCT.The airway parameters and Goddard pulmonary emphysema index were measured.The differences were compared and the correlation with lung function was analyzed.Results The value of 3 rd WA% -5 thwa%of the asthma FL+group was higher than that of the COPD group(P=0.029,0.019,0.002).The value of 3 rd WA% and 5 th WA% of the asthma FL+group were higher than those of the ACO group(P=0.047 and 0.004).The value of 3 rd WT% and 5 th WT% of the asthma FL+group were higher than those of the COPD group and the ACO group(P=0.041,0.032;0.009,0.040).By drawing the receiver operator characteristic curve(ROC curve),it was found that the combination of 3 th WT% +5 th WA%had a better differential value(AUC=0.744,P=0.002,sensitivity=82.4%,specificity=60.9%)between asthma with airflow restriction and ACO.The Goldard index score of the COPD group was higher than that of the ACO group and the asthma FL+group(P<0.001),and the ROC curve analysis showed that Goldard index score had a good differential value for COPD and ACO(AUC=0.777,P<0.001,sensitivity=97.2%,specificity=55.9%).In COPD,ACO and asthma FL+patients,the value of 5 th WA% and 5 th WT% showed a negative correlation with FEV1/FVC(P<0.05).The Goddard score of patients in the three groups was negatively correlated with FEV1/FVC,and the correlation between Goddard score and FEV1/FVC in the ACO patients was statistically significant(P=0.022).Conclusion There are some differences in HRCT findings among the COPD group,the asthma with airflow restriction group and the asthmatic COPD group.The correlation between the parameters of the proximal airway and the emphysema index and the pulmonary function of the patients with ACO is more significant and unique.The automatic quantitative determination of 3 rd WT% combined with 5 th WA% and the emphysema index is helpful for the identification of the subtypes of chronic obstructive pulmonary disease.It has potential clinical value to evaluate the severity of airflow restriction in patients who are unable to complete pulmonary function test.