Persistence of Airway Inflammation and Remodeling in Subjects With Symptomatic or Complete Asthma Remission
This study aims at determining the patterns of asthma remission, the prevalence of these different patterns, the various factors associated with such remissions and possible recurrences of asthma, in order to determine the mechanisms involved in these processes.
The investigators therefore want to document these specificities in 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.
|Study Design:||Observational Model: Case Control
Time Perspective: Prospective
|Official Title:||Characteristics of Symptomatic Asthma Remissions|
|Study Start Date:||September 2007|
|Study Completion Date:||February 2012|
|Primary Completion Date:||June 2011 (Final data collection date for primary outcome measure)|
Complete remission of their asthma
Subjects in complete remission of their asthma Subjects in complete remission of their asthma: absence of respiratory symptoms, no rescue asthma medication need and an optimal pulmonary function and normal PC20 methacholine (>16 mg/ml) for more than two years (with no current treatment).
Symptomatic remission ofasthma
Subjects in symptomatic remission of their asthma (No asthma symptoms in the last 2 years, no asthma medication, PC20 methacholine <16 mg/ml)
Current asthma (mild asthma)
Subjects with current asthma (Mild asthma)
Primary Outcome Measures :
- Airway inflammation (% induced sputum eosinophils)
Secondary Outcome Measures:
- Perception of induced respiratory symptoms
- Airway response to methacholine and AMP, and perception scores
- Diurnal variation in Peak Expiratory Flows
- Profile of regulatory T cells in the peripheral blood
- Changes in these parameters over time (baseline, 6 months, 1 and 2 years)