Validity of Fractional Exhaled Nitric Oxide and Impulse Oscillometry in Patients With Cough Variant Asthma

Zhujiang Hospital

Status: Completed

Conditions: Cough Variant Asthma

Treatments: Diagnostic Test: fractional exhaled nitric oxide(FeNO); Diagnostic Test: impulse oscillometry(IOS)

Study type: Interventional

Funder types: Other

Identifiers

NCT03573284

2018-HXNK-002

Details and patient eligibility

About

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.

Full description

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.

Enrollment: 146 patients

Sex: All

Ages: 18 to 65 years old

Volunteers: No Healthy Volunteers

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.

Trial design

Primary purpose: Diagnostic

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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146 participants in 1 patient group

Asthma group

Experimental group

Description:

Patients with chronic nonproductive cough for more than 8 weeks based on physician's opinion will be subjected to FeNO, impulse oscillometry(IOS) and pulmonary function. Receiver operating characteristic (ROC) curves to evaluate the clinical value of FeNO and small airways indices in CVA diagnosis. The optimal cutoff point for the level of FeNO and IOS is also determined.

Treatment:

Diagnostic Test: fractional exhaled nitric oxide(FeNO)

Diagnostic Test: impulse oscillometry(IOS)