Characteristics Of Nonspecific Lung Function And Predictors Of Its Evolution

Objective:This study intends to analyze the general characteristics of NSPF,discuss the risk factors for the formation of NSPF,and study the risk factors for the progression of NSPF to COPD,so as to improve clinicians 'understanding of NSPF and facilitate clinicians' early detection of high-risk NSPF patients.Early intervention.Methods:Collect the lung function data of the Fourth Affiliated Hospital of Nanchang University from June 1,2014 to January 1,2020,and the inclusion criteria are:(1)FEV1 / FVC> 70%,TLC% pre?80%;(2)Complete clinical data;(3)completed on the same lung function instrument.According to the characteristics of patients with lung function,they were divided into NSPF group,normal lung function group and simple small airway obstruction group.The selection criteria of NSPF group: FEV1 / FVC?70%,TLC% pre?80%,FEV1% pre and / or FVC% pre <80%;The selection criteria of normal lung function group: FEV1 / FVC?70%,TLC % pre?80%,FEV1% pre and FVC% pre ?80%,MMEF,FEF50%,FEF75% are normal or only one item is less than 65%;the inclusion criteria for simple small airway obstruction group: FEV1 / FVC?70%,TLC% pre?80%,FEV1% pre and FVC% pre ?80%,at least two of MMEF,FEF50%,FEF75% <65%.The first step: test the difference between NSPF group and other two groups in gender,age,BMI,number of smokers,and lung function indicators,and then analyze the risk factors of NSPF formation;the second step: select from the above NSPF patients until 2020 NSPF patients who had repeated lung function twice on January 1st were divided into NSPF1,NSPF2,and NSPF3 groups according to whether the first FEV1% pre and FVC% pre were less than 80%.BMI,basic lung function,the difference between before and after lung function index and the difference between the ratio of progression to COPD Changes,RV / TLC abnormalities,and basic lung function were compared.Multi-group comparisons of measurement data that did not meet the normal distribution were tested by multiple independent samples.Count data was applied by chi-square test.P value <0.05 was included.Logistic regression analysis to analyze the risk factors of NSPF progressing to COPD.Result:1.The difference between NSPF and normal lung function,small airway obstructionThis section collected 281 cases of lung function that met the inclusion criteria,with an average age of 60.30 years,a minimum age of 37 years,and a maximum age of 84 years: 90 cases in the NSPF group,107 cases in the small airway obstruction group,and 84 cases in the normal lung function group.The NSPF group and the small airway obstruction group were statistically different in BMI,FEV1% pre,FVC% pre,RV / TLC,FEF75% and MMEF(P <0.05);NSPF group and normal lung function group were smoking,RV / TLC,FEV1% pre,FVC% pre,RV / TLC,FEF75%,FEF50 and MMEF were statistically different(P <0.05).The risk factors for the formation of NSPF are smoking(OR = 3.326;95% CI: 1.616-6.843),MMEF(OR = 1.122;95% CI: 1.064-1.184),FEF50(OR = 1.103;95% CI: 1.038-1.171)),That is,smoking and the presence of small airway lesions are risk factors for the formation of NSPF.2.Differences in lung function in patients with different types of NSPFThis section included 51 patients with NSPF who had repeated lung function twice: 16 patients with NSPF1,9 patients with NSPF2,and 26 patients with NSPF3.There was no statistical difference between the three groups in interval time,gender,BMI,before and after BMI difference,before and after FEV1 difference(P> 0.05),NSPF3 group and NSPF1,NSPF2 group in the first FEV1% pre,first FVC % pre,RV / TLC had statistical difference(P <0.05),NSPF2 group and NSPF1,NSPF3 group had statistical difference in FVC difference before and after each year(P <0.05),in addition,NSPF3 progressed to 7 cases of COPD,NSPF1 progressed to 4 cases of COPD.3.Risk factors of NSPF evolved into COPDRV / TLC group(OR = 7.841 95% CI: 1.231-49.969)and BMI group(OR = 6.622 95% CI: 1.302-33.684)are the influencing factors of NSPF progressing to COPD(P <0.05),that is,the presence of emphysema As well as obese NSPF patients,it is more likely to progress to COPD.Conclusion:1.The lung function of NSPF patients has certain specificity.Compared with people with normal lung function,they have more smokers,and their basic FEV1 and FVC are lower.FEV1% pre,FVC% pre,RV / TLC,FEF75% and MMEF are lower;2.Smoking and the presence of small airway lesions are risk factors for the formation of NSPF;3.The presence of emphysema and obesity are risk factors for NSPF to progress to COPD.