Study On The Correlation Between Fractional Exhaled Nitric Oxide And Assessment Of Chronic Obstructive Pulmonary Disease

Objective(s):To explore the correlation between fractional exhaled nitric oxide(FeNO)value and the severity of chronic obstructive pulmonary disease(COPD).Methods:The study was conducted in the Department of Respiratory and Critical Care Medicine,the Fifth Affiliated Hospital of Kunming Medical University.From September 2017 to September 2019,178 patients with stable COPD and 30 volunteers with health check-up were selected.The items of each case we collected included gender,age,nation,smoking history,height,weight,body mass index.All subjects underwent exhaled nitric oxide test and pulmonary function test.Patients with COPD were divided into four subgroups according to the GOLD grading criteria:mild(n=30),moderate(n=78),severe(n=40),and extremely severe(n=30).Then,every patient with COPD was divided into four subgroups A(n=50),B(n=34),C(n=46),and D(n=48).The differences in FeNO values between patients with COPD and healthy groups were compared,as well as the subgroups of COPD.Results:1.The levels of FeNO in patients with COPD[26.00(17.75-44.25)ppb]were significantly higher than in healthy case[20.50(15.00-26.00)ppb].2.178 patients with COPD were graded according to gender,age,nation,smoking history,height,weight,body mass index.In the univariate analyses,FeNO was significantly higher in non-smoker and quitters,than smoker,but didn't differ between non-smoker with quitters.There was also no significant difference between group with different gender,different age,different nation,different height,different weight and different body mass index.After all variables were included for multiple linear regression analysis with the natural logarithm of FeNO.Smoking status were associated positively with FeNO values(P<0.01),the partial regression coefficient is 0.334..But gender,nation,height,weight and body mass index were not associated with FeNO values.3.The levels of FeNO in GOLD grades are30.00(24.00-36.50)ppb,29.00(18.00-43.50)ppb,27.00(18.00-38.75)ppb,22.50(13.75-33.75)ppb There was not significant difference between subgroups.4.The values of FeNO in subgroups A,B,C,and D,which was divided by the comprehensive assessment of COPD,are 24.50(16.75-38.00)ppb,25.00(18.00-36.25)ppb,30.50(19.75-47.25)ppb,28.00(17.25-41.75)ppb.The values of FeNO in group C was significantly higher than the group A.Conclusion(s):1.Smoking is an importantly influenced factor of FeNO.Smoking could reduce the FeNO value of patients with chronic obstructive pulmonary disease.Quitting smoking could increase the FeNO value.2.FeNO level is elevated in patients with stable COPD.Detection of FeNO is helpful for the diagnosis of COPD.3.The difference between subgroups C,and A is the risk of acute exacerbation.According to the results of this study:the group C was significantly higher than the group A.Then,FeNO may be a good indicator to assess the future risk of acute exacerbations in patients with COPD.It is also expected to be a good predictor for guiding patients with COPD to use ICS.4.There was no significant correlation between FeNO and GOLD grades in patients with stable COPD.5.The test of FeNO,it is a useful supplement to the assessment of COPD,should combine with pulmonary function and comprehensive assessment to achieve individualized treatment...