| [Background]Chronic obstructive pulmonary disease(COPD)is a chronic respiratory disorder characterized by irreversible constant airflow limitation and respiratory symptons.It is widely ackonwleadged that the disease is related to the damage of airway or alveoli because of frequent exposure to toxic gas and particles.Harmful external stimuli causes irreversible airway stenosis,inflammation of the airway wall,and emphysema induced by decreased pulmonary elasticity.These pathological changes are characteristic features of the COPD anatomy,which are functionally reflected as irreversible air flow and reduced ventilation.During the pathogenesis of COPD,the inflammation and pathological changes of lung may gradually deteriorate,making it important to have an effective pathological assessment of the disease by imaging methods.COPD is a complex of heterogenous diseases,because the pathogensis behind the disease is complicated and is not yet fully understood,and the disease itself also has a series of clinical phenotype.At present,the assessment of COPD patients are mainly based on GOLD guidelines.Evaluation of airflow limitation according to lung function and GOLD ABCD grouping according to clinical symptoms and the history of acute exacerbations within the past one year,which is a a certain degree of indication of evaluating the patient's condition by the clinician.It is getting more important that clinicians are able to design a personalized program of treatment and rehabilitation for COPD patients based on a comprehensive and multidimensional assessment of the disease.To build a comprehensive multidimensional assessment,we should abandon the idea of assessing the patient's condition based only on pulmonary ventilation function and symptom scores,and turn to a comprehensive assessment system that including basic lung function,symptom performance,quality of life,exercise capacity,nutritional status,and mental health status,which can provide a more realistic understanding of the severity of COPD patients and is more helpful in reflecting the systemic influence of COPD on patients.High-resolution computed tomography(HRCT)is a clinical examination to understand the respiratory status and evaluate the progress of patient's condition.Its high-precision characteristics can overcome the inability of conventional CT in measuring the partial volume effect and breathing movements.The images of bronchus and lung structure are clearly displayed by HRCT,which helps to improve the sensitivity and accuracy of the assessment of the structural changes in respiratory systems.Based on the results of HRCT,the patients were classified into three types according to the degree of emphysema and the bronchial wall thickness.A phenotype is characterized by the absence of emphysema or little emphysema regardless of having bronchial wall thickening.E phenotype is characterized by the presence of apparent emphysema without bronchial wall thickening.M phenotype is characterized by the combination with the presence of apparent emphysema and bronchial wall thickening.So that patients are grouped by pathological changes on the image.HRCT can be included in the comprehensive assessment for patients with COPD,as it serves as a bridge between pulmonary pathological changes and impaired respiratory function.On the other hand,low attenuation area(LAA)scores is the index of low density lesion caused by emphysema in HRCT examination,which is a quantitative indicator of imaging evaluation.Although some scholars have already conducted relevant researches on the application of HRCT in COPD,none of these studies have discussed the application value of HRCT in comprehensive assessment of COPD,nor have they explore the correlation between LAA scores and various comprehensive evaluation indicators.Therefore,this study investigated the relationship between the phenotypes of HRCT and the clinical characteristics of patients with COPD and explored the statistical correlation between LAA scores and comprehensive evaluation indicators.It is of great value for the HRCT to be included in the assessment of patient's condition and rehabilitation management process.[Ojective]This study is a cross-sectional study,mainly through the inclusion of stable COPD patients as subjects,to collect and analyze the relevant examination data of COPD,and to compare the differences of basic clinical data between different imaging phenotypes of COPD patients.The statistical analysis of the differences of the comprehensive assessment system indicators in each imaging phenotype and the correlation between these indicators and the LAA scores were evaluated.All these analysis would provide the basis evidence for the application of HRCT imaging phenotype in the comprehensive assessment system of COPD disease.[Methods]From June 2014 to December 2016,patients who were diagnosed with stable COPD at the Department of Respiratory,Zhujiang Hospital,Southern Medical University were selected as subjects.At the time of enrollment,various types of examination data and imaging examination data related to the condition of COPD were collected and analyzed.Those profiles include:personal data(gender,age,smoking history,height,weight,etc.)and basic clinical features of COPD(disease duration,acute exacerbations in the past year,Body Mass Index,Fat Free Mass Index,basic lung function,respiratory muscle strengh,symptom performance,quality of life,exercise capacity,nutritional status,anxiety and depression condition)and HRCT scan(LAA scores,HRCT classification).SPSS 20.0 was used for statistical analysis of the data.All data were first tested for normality,and normal measurement data were expressed as mean ± standard deviation(x ± s),and count data were expressed as the number of cases(composition ratio).Differences in multiple groups of measurement data were compared using ANOVA one-way analysis of variance for different image phenotype groupings.LSD method or Dunnett T3 method was used for comparison between two groups.Frequency analysis for count data was conducted using chi-square test.Spearman correlation analysis or Pearson correlation analysis was used for the correlation test of two variables;there was a statistically significant difference when the two-sided test was performed at P<0.05.Multiple linear regression was used to evaluate independent factors predicting LAA scores.[Result]1.Basic clinical characteristics of patients with stable COPD during enrollment197 subjects were divided into 3 phenotypes based on HRCT results.There were 50 cases of type A in total,with an average age of 66.30±8.63 years,male/female ratio 30/20,average smoking index(year X number)327.00±434.63,number of hospitalizations in previous year 0.73±1.08,mean LAA grade 0.86±0.35 and LAA score 2.52±1.73,respectively.According to the GOLD stage,12 patients were located in stage ?,31 in stage ?,7 in stage ?,and 0 in stage ?.The patients were grouped into 24 patients in group A according to the GOLD group.10 were in group C,7 in group D and 9 in group D.A total of 101 cases of type E had an average age of 70.38±9.10 years.The gender ratio was 92/9.The average smoking index(year X number)was 646.68±566.83.The number of previous hospitalizations was 1.15±1.26 times.The average LAA score and LAA score were respectively at 2.49±0.58 and 12.34±3.59.The degree of airway obstruction was 3 patients in phase?,34 patients in phase?,50 patients in phase ?,and 14 patients in phase ? based on the GOLD stage.The patients were grouped into 20 patients in group A according to GOLD and group B 30.There were 11 people in group C and 40 in group D.There were 46 cases of M type with a mean age of 68.98±11.02 years,a sex ratio of 40/6,an average smoking index(year X number)of 619.78±667.99,a previous hospitalization of 1.61 ± 1.13 times,and an average LAA rating and LAA score at 2.63±0.64 and 13.46±3.93.The degree of airway obstruction was 3 patients in phase ?,19 patients in phase ?,17 patients in phase ?,and 7 patients in phase IV.The patients were classified into 3 patients in group A and 10 patients in group B according to GOLD.There were 10 people in group C and 23 in group D.The LAA score and grading were statistically significant among the three imaging phenotypes of A,E,and M(P<0.001).In this study,the number of men was significantly more than women,162 males,accounting for 82.2%.The age of type E subjects was higher than that of type A subjects(P=0.032).The smoking index of E and M subjects was significantly higher than that of type A(P<0.001).The number of hospitalizations in the previous year in type M subjects was significantly higher than subjects with type A(P<0.001).Age,smoking index,previous hospitalization times in a year were not statistically different between E and M type.Among the subtypes,subjects with Grade I and II pulmonary function classification accounted for the largest proportion of Type A,accounting for 86.0%,and the proportions of Type E and Type M were relatively small,36.6%and 47.8 respectively.%.Subjects with Grade III and IV pulmonary function classification accounted for 14.0%of Type A,and of Type E and Type M,63.4%and 52.2%,respectively.According to the GOLD grouping A-B-C-D assessment model,subjects in the A group accounted for 68.0%of the A-type and 19.8%and 6.5%of the E and M typerespectively.Subjects in group B accounted for 20%in type A,29.7%in type E,and 21.7%in type M.Subjects in group C accounted for 14%in type A,10.9%in type E,and 21.7%in type M.Subjects in group D accounted for 18%of type A,39.6%of type E,and 50.0%of type M.The results of Chi-square test statistical analysis showed that the distribution of GOLD pulmonary function grading and GOLD grouping in each imaging phenotype was statistically significant(?2,41.386,30.121,P<0.001).2.the characteristics of each imaging phenotype in the comprehensive assessmentType A subjects had a mean FEV of 1.63±0.55 L,FEV1%pred of 70.98±18.79%,FVC of 2.71±0.90L,FEV1/FVC of 60.04±8.36%,MMRC of 1.24±1.17,CAT of 14.961±8.30,and SGRQ 24.40±14.74,6MWD 479.96±91.50 meters,PImax 63.05±17.36 cmH2O,PEmax 75.30±22.35 cmH20,FFMI 16.11±1.63,BMI 23.20±3.27,BODE 1.44±1.46,HADS total score 3.94±2.22 points,HADS depression subscale 1.86±1.28 points,HADS anxiety scale 2.08±1.37 points.The B type subjects had a mean FEV of 1.12±0.48 L,a FEV1%pred of 46.68±18.11%,a FVC of 2.38±0.81L,a FEV1/FVC of 48.17±11.47%,a MMRC score of 2.18±1.20,a CAT score of 17.86±7.79,and a SGRQ score 29.44±14.74 points,6MWD 391.49±117.44 meters,PImax 51.49±16.31 cmH20,PEmax 57.36±18.71 cmH20,FFMI 15.42±2.18,BMI 21.37±3.79,BODE 3.84±2.33,HADS total score 4.14±2.60 points,HADS depression subscale 1.95±1.33 points,HADS anxiety subscale 2.19±1.55 points.Subjects with type C had a mean FEV of 1.08±0.39 L,FEV1%pred of 48.96±18.18%,FVC of 2.36±0.70L,FEV1/FVC of 47.66±13.12%,MMRC score of 2.22±1.09,CAT score of 20.41±7.69,and SGRQ scores.31.53±12.14 points,6MWD 371.46±151.16 meters,PImax 52.69±16.61 cmH20,PEmax 61.09±23.40 cmH20,FFMI 15.71±1.76,BMI 21.01±3.05,BODE 4.28±2.27,HADS score 4.04±2.36 points,HADS depression subscale 1.93±1.40 points,HADS anxiety scale 2.21±1.25 points.There were no significant differences among the three imaging phenotypes in FFMI,HADS scores,HADS depression scores,and HADS anxiety scores(P>0.05).The mMRC and BODE of type A subjects were significantly lower than those of patients of type E and M(P<0.001).The FEV1,FEV1%pred,FEV1/FVC%,6MWD,PImax,PEmax,and BMI were significantly higher than those of the other two groups.Types(P<0.01),these indicators were not statistically different between E and M subjects.In addition,the CAT and SGRQ of type M subjects were higher than those of type A subjects(P<0.05).3.Correlation analysis and multiple linear regression analysis of LAA scores and comprehensive indicatorsAfter spearman correlation analysis or Pearson correlation analysis,it was found that in all subjects,LAA scores was correlated with FFMI(r=-0.146,P=0.041),with FEV1(r=-0.607),mMRC(r=0.512),CAT(r=0.314),SGRQ(r=0.351),6MWD(r=-0.500),PImax(r=-0.439),PEmax(r=-0.438),FFMI(r=-0.146),BMI(r=-0.269)and BODE(r=0.693)were significantly correlated(P<0.001).Multiple linear regression found BODE,FEV1,and BMI to be independent predictors of LAA scores(P<0.01).[Conclusion]This study found that HRCT was applicable to the comprehensive assessment of COPD.Clinical features and the comprehensive assessment were different among groups divided by HRCT phenotypes.Compared to type E and M,type A may have a higher quality of life and a better clinical prognosis.There is a correlation between LAA scores and multiple COPD comprehensive assessment indicators.The HRCT phenotypes and LAA scores can be employed to assess the severity of COPD to a certain extent,which can provide a useful supplement for the comprehensive assessment of disease. |
PDF Full Text Request