Fractional Exhaled Nitric Oxide Test For Assessment Of Therapeutic Effect Of Asthma Treated With Leukotriene Receptor Antagonists

BackgroudThe 2017 Global Asthma Prevention Initiative（GINA）guidelines define asthma as a heterogeneous disease.In recent years,its prevalence has increased year by year,predicted to 2025 asthma patients will increase to 400 million.The incidence of acute asthma in China ranks first in the Asia-Pacific region,so the control of asthma in China is extremely grim.The current guidelines recommend inhaled corticosteroids（ICS）as the most effective anti-inflammatory drugs currently available for the treatment of asthma.Corticosteroids controls airway inflammation through air resistance,reduce airway hyperresponsiveness,reduce airway edema,enhance airway smooth muscleβ₂ receptor reactivity.However,some patients can not achieve asthma control,even if these drugs are used in high doses in monotherapy or in combination with long-actingβ₂ receptor agonists.Leukotriene receptor antagonist montelukast as an additional treatment for corticosteroids can improve asthma control,leading to a reduction in the frequency of acute asthma attacks and the use of short-actingβ₂ receptor agonists and improved lung function.Fractional exhaled nitric oxide（FeNO）is a noninvasive and easy-to-obtain biomarker with a noninvasive,simple and reproducible feature that predicts the development and deterioration of asthma and predicts the treatment response of selected asthma populations and can therefore be used to detect the efficacy of montelukast in the treatment of asthma.ObjectiveEvaluate the clinical efficacy of montelukast in the treatment of bronchial asthma by FeNO test,pulmonary function,asthma control test score,EOS evaluation efficacy,in order to provide a reference indications for asthma patients who still can not achieve asthma controleven if they use high doses corticosteroids in monotherapy or combine with long-actingβ₂ receptor agonists,and to investigate the clinical significance of FeNO in asthma treatment.MethodsWe selected a total of 160 patients who were hospitalized in the Department of Pulmonary and Critical Care Medicine of Qianfoshan Hospital of Shandong Province between January 2016 and July 2017.The entire asthma patients accorded with the guideline of asthma which established by Chinese medical association in 2016.The patients did not use theophy lline、corticosteroid、antihistamines and leukotriene receptor antagonists in the last two weeks.Patients were randomly divided into reguler treatment group and montelukast treatment group,both groups were given conventional therapy such as oxygen inhalation,anti-infection,cough relieving,anti-asthma and treatment of basic diseases,and budesonide suspension（trade name:Pulmicort,2ml:1mg/piece）was inhaled by inhalation treatment,once 1mg twice a day.The montelukast sodium treatment group plus montelukast sodium（trade name Salbutamol,10mg/tablet）for treatment on the basic treatment of the regular treatment group,1 tablet/per night.The levels of FeNO,pulmonary function and ACT before and after treatment were measured in two groups to evaluate the clinical efficacy of montelukast sodium in the treatment of bronchial asthma.Resluts1.The comparison of baseline data between the two groups of reguler treatment group and montelukast sodium treatment group showed no significant difference.There was no significant difference between the two groups in gender,age,height,weight and course of disease（P>0.05）;2.The levels of FeNO and eosinophil（EOS）in the treatment group and the montelukast sodium treatment group decreased significantly（P<0.01）,and the forced expiratory volume in the second second（FEV₁%pred）,Peak expiratory flow（PEF）,and ACT scores increased significantly（P<0.01）.There was no significant difference between the two groups before treatment（P>0.05）,and there is a statistical difference after treatment（P<0.01）;3.A correlation analysis between FeNO and FEV₁%pred,EOS,ACT,and PEF before treatment showed that there was a positive correlation between FeNO and EOS before treatment and a negative correlation with FEV₁%pred（P<0.05）.There was no correlation between FeNO and other variables.4.The correlation analysis between FeNO and FEV1%pred,EOS,ACT and PEF after treatment showed that FeNO was negatively correlated with PEF after treatment（P<0.01）,and there was no correlation with other variables.ACT score and FEV1%Pred was positively correlated（P<0.05）,negatively correlated with EOS（P<0.05）,and positively correlated with PEF（P<0.01）.Conclusion1.Both inhaled glucocorticoids and oral leukotriene receptor antagonists are effective in the treatment of bronchial asthma and are better when combined with a leukotriene receptor antagonist.2.The dynamic monitoring of FeNO level is beneficial for the clinical evaluation of asthma control and the application of asthmatic treatment drugs inhaled glucocorticoid（ICS）and oral leukotriene receptor antagonist montelukast sodium.3.The value of monitoring the exhaled nitric oxide concentration（FeNO）in evaluating the efficacy of montelukast remains to be confirmed in large sample clinical studies in the future.