Analysis Of The Rate Of Pulmonary Function Decline In Patients With Smoking Related Emphysema

Objective:To investigate the effect of airflow obstuction on the rate of lung function decline in patients with smoking related emphysema,Observe and study the difference of natural course of disease between emphysema with and without airflow obstuction,to provide theoretical basis for individual treatment of emphysema.Methods:Taken follow-up study.A total of 189 smoking patients with respiratory symptoms and had significant emphysema on chest CT and finished the measurement of lung function at the same time were selected in our hospital from 2017 to 2019.Adopt standards set by the Global Initiative for Chronic Obstructive Pulmonary Disease(GOLD),the patients were divided into two groups :with and without airflow obstuction group.Then followed up those patients from May to December in 2019,lung function were retested,the clinical characteristics were recorded by questionnaire.FEV1 or FVC decline in L,as of baseline(%B)was calculated.The patients were divided into two groups of follow-up one year group and two years group on the basic of the follow-up time.Patients were compared in the same follow-up period,the general datas and the changes of FEV1 and FVC in the two groups were compared by t-test / chi square test.Results :Due to the interruption of communication,inconvenience of transportation,and refusal of patients with poor follow-up awareness,53 patients were finally followed up,among them,33 cases were emphysema without airflow obstuction,20 cases were emphysema with airflow obstuction.There was no significant difference in severity of emphysema,number of acute exacerbations,sex,age,body mass index and smoking index between the two groups.When the period of follow-up was one year,in the without airflow obstuction group the mean change of FEV1 was-0.2L(-6.53%B),and the mean change of FVC was-0.12L(-6.27%B).In the airflow obstuction group the mean change of FEV1 was-0.11L(-8.5%B),and the mean change of FVC was-0.15L(-6.27% B).When the period of follow-up was two years,in the without airflow obstuction group the mean change of FEV1 was-0.25L(-8.08%),and the mean change of FVC was-0.2L(-4.62%B).In the airflow obstuction group the mean change of FEV1 was-0.26L(-17.5%B),and the mean change of FVC was-0.36L(-12.79%B),of them,FEV1%Band FVC%B were significantly different between the two groups(P = 0.028,P = 0.036 <0.05).FEV1 and FVC of the group with airflow obstuction had faster decline.Conclusions:Patients with smoking related emphysema and respiratory symptoms,whether there is airflow restriction or not has no significant effect on the rate of pulmonary function decline during one year follow-up.At one-year follow-up,the rate of pulmonary function decline was faster in patients with airflow obstruction.