Bronchoscopy With Bronchial Biopsies Sub-study of: Persistence of Airway Inflammation and Remodeling in Asthma Remission

Bronchoscopy and Bronchial Biopsies. Sub-study of: Characteristics of Asthma Remissions

This study aims at determining the patterns of asthma remission, the prevalence of these different patterns and the various factors associated with such remissions and possible recurrences of asthma, in order to determine the mechanisms involved in these processes.

We therefore want to document these specificities in studying biopsies of subjects in complete remission of their asthma and those in only symptomatic remission of their asthma, in comparison with mildly symptomatic asthmatic subjects and healthy controls.

Primary Outcome Measures :

Airway inflammation and remodeling: in bronchial biopsies

Secondary Outcome Measures:

Comparisons of bronchial biopsy features between groups:

• Bronchial epithelial morphology
• Bronchial mucosa (smooth muscle, reticular basement membrane, submucosal gland,...)

Inclusion Criteria:

• In remission of their asthma: absence of respiratory symptoms, no rescue asthma medication need and (for complete remission) an optimal pulmonary function (FEV1 > 90%) and normal PC20 methacholine for more than two years (with no current treatment).
• With a proven past history of asthma from medical files (reversible airway obstruction (> 12% FEV1 after bronchodilator or 20% by other means) proven by spirometry, PEF measures or methacholine challenge according to current criteria + previous symptoms and asthma medication use), having no more asthma symptoms and not having used asthma medication for more than 2 years.
• Agree to sign the consent form.
• No other condition that could interfere with the study measurements.

Exclusion Criteria:

• Subjects using inhaled or oral anti-inflammatory agents.
• FEV1 < 1.2 L.
• Unable to adhere to the protocol requirements.
• Other current respiratory disease
• Upper or lower respiratory tract infection or use of antibiotics < 1 month.
• Use of oral corticosteroids within the last 3 months.
• Signs or symptoms of progressive or uncontrolled renal, hepatic, hematologic, endocrine, pulmonary, cardiac, neurologic or cerebral disease.