Clinical trial NCT03102749: Mechanism and Dynamics of Bronchial Hyper-reactivity to Methacholine in Distal Airway on Obese Patients With Asthma
Official title: Mechanism and Dynamics of Bronchial Hyper-reactivity to Methacholine in Distal Airway on Obese Patients With Asthma
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Asthma
Keywords: Airways
asthma
overweight
Lead sponsor: University Hospital, Montpellier
Sponsor class: OTHER
Collaborators: name: Centre Hospitalier Universitaire de Nīmes
First posted: 2017-04-06
Enrollment: 35
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 85
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_CONTROL
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients will be recruited in the respiratory department of University Hospital in Montpellier (France) from June 2012 to March 2014. All patients are asthmatics, in order to avoid any gender-related biases, investigators decided to include only women. All participants had normal range spirometry, specifically regarding forced expiratory volume.

Brief summary: New insights of small airway contribution to asthma have been gained. Poor levels of control and recurrent exacerbations were shown to have the phenotypic counterpart of asthma with predominant small airway involvement. Very few pathological specificities were identified at this site: mast cells infiltration was suggested as the specific inflammatory change when compared to the proximal airways.Biomarkers in asthma are still complex to validate, especially in the blood, since compartmentalisation is intense in the lung and the airways, a property attributed to the filtering role of the lung to maintain homeostasis. Over the last few years, Fraction exhaled Nitric Oxide (FENO) was developed as a non-invasive and indirect reflection of airway eosinophilic inflammation\]. In the blood, peripheral eosinophil counts were shown as a correct T helper 2 (TH2)-phenotype identifier but not perfectly related to airway eosinophilic infiltration. Club cell secretory protein (SCGB1A1) levels have been shown to have some relevance in asthma, chronic obstructive pulmonary disease (COPD), BOS, sarcoidosis, and lung cancer.A biomarker for small airway disease in asthma may improve the management of the disease, identify areas of therapeutic resistance and constitute a therapeutic guidance tool. In this study, investigators aimed to assess small airway involvement in asthmatic women as far as they could. For this purpose, investigators analysed trends in air trapping by acquiring expiratory CT slices at each dose during a bronchoprovocation test with metacholine. Biomarkers were subsequently tested and confronted to clinical and demographical characteristics in their ability to predict the small airway involvement index obtained at CT.

Detailed description: Patients will be recruited in the respiratory department of University Hospital in Montpellier (France) from June 2012 to March 2014. All patients are asthmatics, in order to avoid any gender-related biases, investigators decided to include only women. All participants had normal range spirometry, specifically regarding forced expiratory volume. Each patient will undergo a bronchial provocation test coupled with a thoracic CT scan. Bronchial and alveolar Nitric Oxyde will also be measured, a blood sample will be obtained in order to measure biomarker concentrations, and the patients will be asked to answer the validated Asthma Control Questionnaire in order to quantify asthma control.

Eligibility criteria: Inclusion Criteria:

* Female \>= 18 yrs
* Asthma
* Treated with Inhaled Corticosteroid (ICS)
* normal range spirometry

Exclusion Criteria:

* Patients with other respiratory disease
* Patients with myocardial infarction (for 3 month before enrollment)
* Patients with cerebrovascular accident (for 3 month before enrollment)
* Patients with arterial aneurysm known
* Patients in pregnancy
* Patients nursing

Primary outcomes:
measure: Change in inspiratory:expiratory mean lung density
timeFrame: 4 hours (after the enrollment)
Secondary outcomes:
measure: Change in lung fractal dimension
timeFrame: 4 hours (after the enrollment)
measure: Bronchial morphometry
timeFrame: Baseline
measure: CC10 level
timeFrame: Baseline
measure: FeNO
timeFrame: Baseline
measure: FaNO
timeFrame: Baseline
Other outcomes:
Locations:
city: Montpellier
country: France
facility: Department of respiratory disease
Study officials:
affiliation: University Hospital, Montpellier
name: Arnaud BOURDIN, MD
role: PRINCIPAL_INVESTIGATOR
References: