Evaluating the Efficacy of Fractional Exhaled Nitric Oxide and Impulse Oscillometry in Patients With Cough Variant Asthma
Evaluating the Efficacy of Fractional Exhaled Nitric Oxide and Impulse Oscillometry in Patients With Cough Variant Asthma
The aim of the research is to evaluate the clinical value of fractional exhaled nitric oxide(FeNO) ,impulse oscillometry(IOS) and mid-expiratory flow (MEF) in patients with cough variant asthma.
The present study has the following objectives:
to evaluate the relationship between BHR and mid-expiratory flow, to assess the diagnostic accuracy of fractional exhaled nitric oxide，impulse oscillometry and mid-expiratory flow in CVA with special regard to its discriminating value between CVA and other causes of a chronic cough, to estimate prognostic value of BHR and fractional exhaled nitric oxide (FeNO) count in predicting response to asthma treatment.
Inclusion Criteria:
age 18-65 years old. Cough as the sole or predominant symptom lasting for at least 8 weeks, with no radiographic evidence of lung diseases.
Exclusion Criteria:
treatment of any oral corticosteroid in the last 4 weeks, and respiratory tract infection within 8 weeks.
smoking (min. 6 months) had asthma or other lung diseases, including obliterative bronchiolitis, bronchiectasis,and cystic fibrosis.