SCANN'AIR: Mechanism and Dynamics of Bronchial Hyper-reactivity to Methacholine in Distal Airway on Obese Patients With Asthma
Study Details
Study Description
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.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
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.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Normal weight Included patients with a BMI < 25 will be part of this group. |
Other: metacholine provocation test and CT-scan low dose
Investigators perform a metacholine provocation test where expiratory CT slices were acquired at each dose
|
| Overweight Included patients with a BMI >= 25 and <30 will be part of this group. |
Other: metacholine provocation test and CT-scan low dose
Investigators perform a metacholine provocation test where expiratory CT slices were acquired at each dose
|
| Obese Included patients with a BMI >= 30 will be part of this group. |
Other: metacholine provocation test and CT-scan low dose
Investigators perform a metacholine provocation test where expiratory CT slices were acquired at each dose
|
Outcome Measures
Primary Outcome Measures
- Change in inspiratory:expiratory mean lung density [4 hours (after the enrollment)]
Baseline versus post-methacholine challenge
Secondary Outcome Measures
- Change in lung fractal dimension [4 hours (after the enrollment)]
Baseline versus post-methacholine challenge
- Bronchial morphometry [Baseline]
Analysis of CT imaging
- CC10 level [Baseline]
Clara cell 10 kD protein levels in blood
- FeNO [Baseline]
Exhaled nitric oxide level
- FaNO [Baseline]
Alveolar nitric oxide level
Eligibility Criteria
Criteria
Inclusion Criteria:
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Female >= 18 yrs
-
Asthma
-
Treated with Inhaled Corticosteroid (ICS)
-
normal range spirometry
Exclusion Criteria:
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Patients with other respiratory disease
-
Patients with myocardial infarction (for 3 month before enrollment)
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Patients with cerebrovascular accident (for 3 month before enrollment)
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Patients with arterial aneurysm known
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Patients in pregnancy
-
Patients nursing
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Department of respiratory disease | Montpellier | France | 34295 |
Sponsors and Collaborators
- University Hospital, Montpellier
- Centre Hospitalier Universitaire de Nīmes
Investigators
- Principal Investigator: Arnaud BOURDIN, MD, University Hospital, Montpellier
Study Documents (Full-Text)
None provided.More Information
Additional Information:
Publications
None provided.- 8836
- 2011-A01396-35