定量CT测量对老年慢性阻塞性肺疾病患者肺功能的预测价值分析

Analysis on the predictive analysis of quantitative CT measurement for pulmonary function of elderly patients with COPD

目的:分析定量CT(QCT)测量对老年慢性阻塞性肺疾病(COPD)肺功能的预测价值。方法:选取医院收治的100例老年COPD患者,均行肺功能检查(PFT)及CT检查,测量并对比不同严重程度COPD患者QCT指标气管气道壁厚度(WT)、气道壁厚度与截面半径比值(TDR)、管壁面积百分比值(WA%)及低衰减区面积百分比(LAA%)的差异;采用Pearson相关性分析检验上述QCT指标与患者肺功能指标及COPD评估测试(CAT)评分的相关性;采用受试者工作特征(ROC)曲线评估单一参数、双参数、三参数及四参数联合对上述患者COPD不同严重程度的预测价值。结果:随着老年患者COPD严重程度的增加(从轻度、中度、重度到极重度),患者上肺区、中肺区及下肺区的QCT参数WT、TDR及WA%随之增加,差异均有统计学意义(F_(WT)=17.231,F=14.829,F=13.810;F_(TDR)=12.881,F=13.902,F=14.832;F_(WA%)=23.842,F=24.906,F=27.693;P<0.05);轻度、中度、重度到极重度患者两肺、左肺及右肺LAA%值呈上升趋势,差异有统计学意义(F=13.642,F=14.731,F=11.803;P<0.05)。COPD患者QCT参数WT、TDR、WA%及LAA%与中度、重度COPD患者CAT评分具有显著相关性(r=0.394,r=0.473,r=0.501,r=0.462;r=0.532,r=0.552,r=0.492,r=0.602;P<0.05),WT及LAA%与患者整体CAT评分具有显著相关性(r=0.438,r=0.302,r=0.267,r=0.543;P<0.05);进一步探索QCT指标与COPD患者肺功能指标的相关性,WT、TDR、WA%及LAA%与FEV1/FVC、FEV1%均呈明显的负相关关系(r=-0.733,r=-0.742,r=-0.708,r=-0.693;r=-0.678,r=-0.595,r=-0.584,r=-0.604;P<0.05);WT、TDR、WA%及LAA%四项参数联合对老年COPD患者的肺功能预测的ROC曲线下面积(AUC)为0.889。结论:QCT参数与老年COPD患者的肺功能存在明显相关性,WT、TDR、WA%及LAA%联合对患者的肺功能具有良好的预测价值。

Objective:To analyze the predictive value of quantitative computed tomography(QCT)measurements on the pulmonary function of elderly patients with chronic obstructive pulmonary disease(COPD).Methods:A total of 100 elderly patients with COPD were selected,and all of them underwent pulmonary function test(PFT)and CT examination.The walls thickness(WT)of tracheal airway,thickness-diameter ratio(TDR)of airway wall,percentage of wall area(WA%)and percentage of low attenuation area(LAA%)of QCT indicators of COPD patients with different severity levels were measured and the differences of them were compared.The Pearson correlation analysis was adopted to test the correlations between above QCT indicators and the indicators of pulmonary function,and the scores of COPD assessment test(CAT).The receiver operating characteristic(ROC)was adopted to assess the predictive value of the combination of single parameter,dual parameter,triple parameter and quad parameter for the different severity levels of the COPD of above patients.Results:With the increasing of COPD severities of elderly patients(from mild,moderate,severe to extremely severe level),the WT values,TDR values and WA%values of QCT parameters of upper lung area,middle lung area and lower lung area of patients increased,and the differences were significant(F_(WT)=17.231,F=14.829,F=13.810,F_(TDR)=12.881,F=13.902,F=14.832,FWA%=23.842,F=24.906,F=27.693,P<0.05),respectively.The LAA%values of dual lungs,left lungs and right lungs of patients with mild,moderate,severe and extremely severe levels appeared upward trend,and the differences were significant(F=13.642,F=14.731,F=11.803,P<0.05),respectively.The WT value,TDR value,WA%value and LAA%value of QCT parameters of COPD patients were significant correlations with CAT scores of moderate and severe COPD patients(r=0.394,r=0.473,r=0.501,r=0.462,r=0.532,r=0.552,r=0.492,r=0.602,P<0.05),respectively.The WT value and LAA%value were significant correlations with overall CAT scores of patients(r=0.438,r=0.302,r=0.267,r=0.543,P<0.05),respectively.In the results of the further explorations for the correlations between QCT indicators and pulmonary function indictors of COPD patients,the WT,TDR,WA%and LAA%appeared significantly negative correlations with FEV1/FVC,FEV1%(r=-0.733,r=-0.742,r=-0.708,r=-0.693,r=-0.678,r=-0.595,r=-0.584,r=-0.604,P<0.05),respectively.The under-curve area(AUC)value of the combination of WT,TDR,WA%and LAA%was 0.889 in predicting the pulmonary function of COPD elderly patient.Conclusion:There are significant correlations between QCT parameters and pulmonary function in COPD elderly patients,and the combination of WT,TDR,WA%and LAA%has favorably predictive value for the pulmonary function of patients.