Measurement of Exhaled Nitric Oxide (NO) and Bronchial Provocation Test With Mannitol as a Predictor of Response to Inhaled Corticosteroids in Chronic Cough

Condition(s) targeted: Cough; Bronchial Hyperreactivity

Intervention: bronchial provocation test with mannitol (Procedure)

Phase: N/A

Status: Completed

Sponsored by: Centre Hospitalier Universitaire de Saint Etienne

Official(s) and/or principal investigator(s):
Frédéric COSTES, MD PhD, Principal Investigator, Affiliation: CHU de Saint-Etienne

Chronic cough is defined by its persistence beyond 8 weeks. Many conditions can explain the existence of a bronchial inflammation. In the management of chronic cough, the search for bronchial hyperreactivity (HRB) is recommended. The treatment relies primarily on the prescription of inhaled corticosteroids. It has been shown recently that the existence of an HRB with Methacholine (bronchial provocation test used in routine) does predict the effectiveness of inhaled corticosteroid treatment in no more than 50% of cases. It is now possible to assess the bronchial inflammation by rapid, non-invasive and reproducible tests such that the fraction of exhaled nitric oxide (FeNO) and bronchial provocation test with mannitol. In a retrospective study, it was shown that an increased value of FeNO (cut-off > 35 ppb) predicts a positive response to treatment with a sensitivity of 90% and a specificity of 80%.

Official title: Measurement of Exhaled NO and Bronchial Provocation Test With Mannitol as a Predictor of Response to Inhaled Corticosteroids in Chronic Cough

Study design: Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Diagnostic

Primary outcome: The intensity of coughing on a 10-cm visual scale

Secondary outcome:

Sensitivity, specificity, positive predictive value and negative predictive value of the threshold value of 35 ppb FeNo to the clinical response seen as positive if the EVA reduces cough of at least 2 cm

Sensitivity, specificity, positive predictive value and negative predictive value of response to bronchial provocation test with mannitol on the clinical response seen as positive if the EVA reduces cough of at least 2 cm

Correlation between the value of FeNo and dose of mannitol causing a fall of 15% of maximum volume expired second (PD15)

Score quality of life of the Leicester Cough Questionnaire

Detailed description: The purpose of this study is to show that the use of the prospective value of exhaled NO can predict response to treatment with inhaled corticosteroids in adult with chronic cough. In addition we will assess the interest of the prognosis of bronchial provocation test with mannitol in this indication.

Minimum age: 18 Years. Maximum age: N/A. Gender(s): Both.

Criteria:

Inclusion Criteria:

- Chronic Cough during 2 months

- Social Security regimen affiliated

- Consent form signed

Exclusion Criteria:

- Smoking active

- Treatment with angiotensin converting enzyme inhibitor

- Clinical signs of obvious gastroesophageal reflux

- Clinical rhinosinusitis

- Recent respiratory infection (< 1 month)

- Corticosteroid Treatment(oral or inhaled) within 2 weeks

- VEMS < 1 L or < 80% of the theoretical value

- Existence of an obstructive ventilatory disorder defined as a report (FEV/FVC) < 90%

of the theoretical value

CHU de Saint-Etienne, Saint-Etienne 42055, France

Starting date: November 2008
Last updated: November 23, 2010