The Value Of Fractional Exhaled Nitric Oxide In The Treatment Of Chronic Cough

Objective:As a common,frequently-occurring disease in respiratory clinics,chronic cough are often misdiagnosed as other diseases in the clinic due to its complex disease.The patient used drugs repeatedly with little effects.The long-term cough itself brings great harm to the patient,and also causes a considerable waste of medical resources.Due to showing sensitivity to the treatment of glucocorticoid,cough variant asthma,eosinophilic bronchitis,allergic cough are called as glucocorticoid-sensitive cough,and account for the most of chronic cough patients in China,they are mainly chronic eosinophilic inflammation of the airways.In terms of chronic cough,there is disagreement among domestic and foreign doctors on whether FeNO could guide the use of glucocorticoid therapy for chronic cough.This article intends to evaluating the situation of the airway inflammation in patients with chronic cough by detecting exhaled nitric oxide.With performing outpatient follow-up after symptomatic treatment with budesonide-formoterol compound and evaluating the factors that influence the therapeutic effect of patients to explore the value of exhaled nitric oxide in the outpatient department and provide a basis for the use of FeNO to guide glucocorticoids in outpatients with chronic cough.Methods:A prospective study was conducted to collect the medical history,nasopharynx,chest X-ray,cardiac ultrasound,and pulmonary function tests from October 2016 to May 2018 in our respiratory medicine clinic.FeNO,cough visual analog score,and cough symptom score were assessed,all patients were given inhaled budesonide formoterol compound treatment,with a 160/4.5ug per dose oral inhalationof one puff twice daily and follow-up weekly to recording cough visual analog score and cough symptom score.According to comparison with initial score,they were divided into valid and invalid groups after 4 weeks.Firstly,the clinical history and related laboratory results of the two groups of patients were compared to find the characteristics between the two groups.Secondly,seek out the factors that influence the different treatment outcomes of patients.Finally,the optimal FeNO value in chronic cough hormone therapy was sought.Results:In total,there were 133 patients,105 were effective and 28 were ineffective.The FeNO value 45 ppb in the valid group was significantly higher than that in the invalid group 26ppb(P<0.05),and the factors affect the treatment outcome were using binomial logistic regression analysis.FeNO value was the independent risk factors in outcome of treatment.[OR=1.043,95% CI(1.013 to 1.074)].The area under the receiver operating characteristic(ROC)curve was 0.756,and the optimal FeNO cutoff value was37 ppb with the sensitivity of 61%,specificity of 82.1%.Conclusions: FeNO value can be used as an important guider for chronic cough patients.The cut-off point of FeNO value for treatment is 37 ppb and more than the37 ppb,which has a more significant effect on inhaled budesonide formoterol compound treatment.