Small Airway Inflammation and Dysfunction in Different Asthma Phenotypes

Small Airway Inflammation and Dysfunction in Different Asthma Phenotypes

Small airway inflammation and dysfunction will be measured in 40 children and 40 adults with asthma before and after 8 weeks of treatment with inhaled budesonide. The same measurements will be conducted once in 80 age and sex matched healthy controls.

Inclusion Criteria:

• symptoms of asthma and objective evidence of variable or reversible airway obstruction according to at least one of the following criteria
• significant response to bronchodilator (in subjects 7 years or older: FEV1 (forced expiratory volume in 1st second) or FVC (forced vital capacity) increases at least 12 % and 200 ml; in 4-6 years old subjects R5 decreases at least 40 %)
• in at least 12 years old subjects significant diurnal variation (at least 20 % and 60 l/min on at least three days) or significant response to bronchodilator ( at least 15 % and 60 l/min on at least three occasions) in PEF (peak expiratory flow) during a two-week monitoring
• significant airway hyperreactivity (PD20 FEV1 of methacholine less than 600 µg in at least 16 years old subjects, FEV1 decreases at least 15 % in exercise test in 7-15 years old, or R5 increases at least 40 % during free-running test in 4-6 years old subjects)

Exclusion Criteria:

• current smoking
• regular anti-inflammatory asthma medication (will be paused for at least 4 weeks before enrollment)
• other chronic pulmonary disease
• other diseases that in the opinion of the treating physician prevents participation