Evaluate The Efficacy Of Questionnaire Survey Combined With Peak Expiratory Flow Rate (PEF) Method On Chronic Obstructive Pulmonary Disease Screening

Objective:To investigate the main risk factors of chronic obstructive pulmonary disease(COPD)in the community through questionnaires,and to explore the effectiveness and feasibility of the revised screening questionnaire combined with peak flow rate(PEF)measurement as a screening tool for COPD in China.Methods:A total of 378 physical examination patients of the Phoenix Community Health Service Center,Baota District,Yan'an City,from June 2017 to August 2017,aged40 years or older were selected.Subjects were followed by physical examination,COPD risk factor questionnaire and revised COPD screening questionnaire,peak flow meter peak expiratory flow rate and lung function tests.Then,subjects were divided into COPD group and non-COPD group according to the results of lung function.COPD group was divided into GOLDI~IV group furtherly according to the airflow limitation:(1)the basic information and disease-related factor of COPD group and non-COPD group were compared and screened to identify the risk factors among the investigation population;(2)the correlation of the two screening tools and the two main indicators of pulmonary function testing,FEV1/FVC and FEV1%,were compared to determine whether FEV1/FVC and FEV1%can replace lung function as a tool for screening COPD and assessing the severity of the disease;(3)the specific evaluation indicators of two screening tools between COPD and non-COPD groups and GOLDI~IV groups were compared to explore the efficacy on COPD screening and diagnosis.If FEV1/FVC and FEV1%are efficient for the diagnosis of COPD,the receiver operating characteristic curve(ROC curve),the best diagnostic threshold,sensitivity,and specificity were valued respectively.Results:1.General situation1.1 Basic conditions:A total of 395 subjects were included,with 378 effective cases and an effective rate of 95.7%.Of the 378 subjects enrolled,245 were male(64.8%)and 133 were female(35.2%),aged 45-84 years,with an average age of 61.00±10.96years;the average age of COPD group was 68.85±10.81 years.Subjects'academic qualifications were mainly in primary schools and below,with a ratio of 31.7%;COPD group academic qualifications were the highest in elementary schools and below,reaching 56.9%;non-COPD groups were slightly higher in junior high school students,approximately 29.7%.The mean BMI of the study population was 25.44±3.41 kg/m ~2;the average BMI in the COPD group was 23.19±3.60 kg/m ~2;the average BMI in the non-COPD group was 25.90±3.18 kg/m ~2.169 cases were smokers in the study,the smoking rate was 44.7%,the total smoking index was 23.45±18.19 years;the COPD group smokers were 92.3%,the smoking index was 33.20±21.96,and the non-COPD group was about 34.8%.The smoking index was 18.08±13.09 pack-years;only 30.8%of all smokers had quit smoking,and the COPD group quit smoking rate was about 35.0%.1.2 Prevalence:65 subjects with COPD were detected.The total prevalence rate was17.2%,of whom 20.4%was male,which was significantly higher than female 11.3%.According to the GOLD classification standard,the proportions of GOLDI,II,III,and IV were 20.0%,43.1%,35.4%,and 1.5%,respectively.The proportion of early-stage patients(grades I and II)was 63.1%.COPD asymptomatic patients accounted for33.8%,only 66.2%had symptoms and symptoms were not typical.The main proportions were cough,sputum,and asthma.The specific proportion was 39.5%,44.2%,88.4%,and cough cough was 27.9%.Symptoms of COPD patients were mainly grade I and II,about81.8%,and grade III asymptomatic patients accounted for 18.2%of the group.1.3 Diagnosis and treatment of diseases:Only 4.8%of the 378 subjects had had pulmonary function tests.Only 13 cases of patients diagnosed with this disease had previous history of chronic bronchitis or emphysema.COPD was diagnosed in 4 cases,and the rate of missed diagnosis of COPD reached 73.8.%.Most of the missed patients were COPD early patients,accounting for 62.5%,and 35.4%of the missed patients had no symptoms.2.Analysis of risk factors2.1 Univariate analysis of COPD group and non-COPD group:gender,age,smoking history,smoking index,BMI,educational background,occupational dust/smoke exposure history,etc.were statistically significant(P<0.05),and the older COPD population The higher the prevalence rate was,the higher the prevalence rate was with the increase of smoking,with the decrease of BMI and education(P<0.5),but there was no significant difference in heating materials,cooking materials and whether there was a history of allergies(P).>0.05).2.2 Multiple Logistic Regression Analysis:It is clear that men,old age,low BMI,smoking,low education,occupational dust/smoke exposure history are the main risk factors for COPD.3.Screening results of two screening indicators3.1 The performance of two screening indicators to distinguish performance:COPD patients peak flow rate PEF%pred and questionnaire total score of Z were 65.05±19.64%,24.46±5.84 points,non-COPD patients were 117±29.45%,13.19±5.25points,two groups of patients The difference between the peak flow rate PEF%pred and the questionnaire total score Z value was statistically significant(<0.01),indicating that the two screening indicators can better distinguish between COPD and non-COPD.3.2 Correlation analysis between two screening indicators and lung function:Peak flow rate PEF%pred was highly positively correlated with FEV1/FVC(r=0.821,P<0.01),and it was significantly positively correlated with FEV1%(r=0.725,P<0.01).The Z value of the revised screening questionnaire was significantly negatively correlated with FEV1/FVC(r=-0.586,P<0.01),and had no significant correlation with FEV1(P>0.05).3.3 Evaluation indicators of the two screening tools:The sensitivity,specificity,+LR,-LR,correct diagnostic index,positive predictive value,and negative predictive value of the revised COPD screening questionnaire were 84.6%,75.7%,and 3.48,respectively.,0.20,0.60,42.0%,96.0%;the sensitivity,specificity,+LR,-LR,correct diagnosis index,positive predictive value,and negative predictive value of peak flow meter PEF were:76.9%,84.7%,5.02,0.27,respectively,0.62,51.0%,94.6%;sensitivity,specificity,+LR,-LR,correct diagnosis index,positive predictive value,and negative predictive value when the two screening tools were connected in series were:96.9%,67.1%,3.00,0.05,0.65,38.0%,and 99.1%;sensitivity,specificity,+LR,-LR,correct diagnosis index,positive predictive value,and negative predictive value when the two screening tools were connected in parallel were:64.6%,93.3%,8.73,0.44,0.52,66.7%,93.3%.3.4 ROC Curve3.4.1 Area under the ROC Curve of the Two Screening Tools(AUC-ROC):The revised AUC-ROC for the COPD Screening Questionnaire was 0.904;the PEF%pred AUC-ROC for the peak flow meter was 0.912;-ROC was 0.927;AUC-ROC was 0.893in parallel between the two screening tests,and the area under the curve was not statistically significant(P>0.05).3.4.2 The best cut-off point for the two screening tools:When the PEF cut-off point of the peak flow meter is 80%and 90%,the comprehensive screening ability is good.When the cut-off point is 80%,the sensitivity is 76.9%and the specificity is 84.7%.The correct diagnosis index was 0.62,and 30.8%mild airflow limitation patients were identified,85.7%moderate airflow limitation patients,100%severe and extremely severe patients;sensitivity was 84.6%,specificity 66.1,when the cutoff point was 90%%,a correct diagnosis index of 0.51,can identify 46.2%of patients with mild airflow limitation,89.3%of patients with moderate airflow limitation,100%severe and extremely severe patients.However,when the cut-off point of the peak flow rate instrument PEF is 80%,the sensitivity is lower than the specificity.When the cut-off point is 90%,the sensitivity is higher than the specificity,and the sensitivity to GOLDI and II levels increases,and more early patients can be found.If we continue to increase the cut-off point,the specificity of the screening and the correct diagnostic index will be significantly reduced,so the best cut-off point is 90%.The revised COPD screening questionnaire cut-off points were 16.5 points and 17.5 points,with good screening results.Sensitivity,specificity,and correct diagnosis index were:84.6%,75.7%,and 0.60 when the cut-off point was 16.5 points;When the cut-off point was 17.5 points,the above indexes were:83.1%,82.7%,0.66,so the revised COPD screening questionnaire?17.5(18)points as the best cutoff point of COPD,can obtain better screening results.3.5.Screening of COPD by two screening tools under different conditions:Using Peak Velocimetry to detect:COPD patients with different GOLD levels have different sensitivities:30.8%mild,78.6%moderate,severe and very severe%,The sensitivity of patients with different degrees of COPD was not exactly the same(P<0.01).Further comparisons between them showed that the sensitivity of the peak flow meter PEF screening increased with the severity of the disease;the peak flow meter could detect59.1%asymptomatic In patients with COPD,the sensitivity of symptomatic patients increased to 86.0%,the difference was statistically significant(P<0.01);the sensitivity of smoking COPD group and non-smoking COPD group was 80.0%and 40.0%,the difference was not statistically significant(P>0.05).Screening using the revised screening questionnaire:The sensitivity was different in different conditions,with mild76.9%,moderate 85.7%,severe 87.0%,extremely severe 100%,and the sensitivity was not related to the degree of airflow limitation(P>0.05);The sensitivity of symptomatic COPD group and asymptomatic COPD group was divided into 93.0%and 68.2%,the difference was statistically significant(P<0.01);the smoking COPD group detection rate was 88.3%,significantly higher than the non-smoking COPD group 40%,the difference was statistically significant(P<0.01).Conclusion:1.Screening for high-risk groups of community COPD can obtain higher detection rate.The confirmed patients are mainly patients with early COPD,and nearly 1/3 patients have no obvious symptoms.Some patients even lose more than 50%of their lung function.There is still no obvious symptoms,combined with low prevalence of pulmonary function tests,so the rate of missed diagnosis of COPD in the community is very high.The screening of COPD for high-risk groups will help increase the detection rate of COPD,reduce the rate of missed diagnosis in early and asymptomatic patients,and increase the rate of early intervention.2.There are many risk factors for COPD in the community.The population of men,old age,low BMI,smoking history,low education,occupational dust/smoke exposure,etc.,are significantly more likely than the general population.It is necessary to increase community awareness of COPD risk factors,increase awareness of early disease prevention,and strengthen and implement tobacco control strategies.3.The peak flow meter PEF and the revised screening questionnaire are more effective in identifying the effectiveness of COPD and comprehensive diagnostic ability,and can be used as an effective means for the initial screening of high-risk groups of COPD in China,especially when the two screening tools are in series.Early COPD patients were found and the rate of missed diagnosis was reduced.In China,the peak cut-off point of PEF was 90%,and the optimal cut-off point of the revised screening questionnaire was 17.5(18)points.4.The sensitivity of PEF screening increased with the exacerbation of COPD,the sensitivity of symptomatic populations was significantly higher than that of asymptomatic individuals,there was no difference in the sensitivity of smoking and non-smoking populations;the revised screening questionnaire was The sensitivity of patients with different degrees of COPD is better,especially suitable for the screening of smoking history and symptomatic population.Compared with PEF,the revised screening questionnaire is more sensitive to mild airflow limitation and asymptomatic patients.