The Effect of Atopy and Airway Eosinophilic Inflammation on Exercise-Induced Bronchospasm in Asthmatics / 소아알레르기및호흡기학회지

ABSTRACT

PURPOSE: Exercise-induced bronchospasm (EIB) is widely prevalent in asthmatic patients. Recently, eosinophilic airway inflammation and atopy (defined as skin sensitivity to common aeroallergens) are considered to be a important factors in the pathogenesis of asthma. Thus we studied to find out the effect of atopy and airway eosinophilic inflammation on exercise- induced bronchospasm. METHODS: We followed up the cases of 132 mild asthmatics for 2 years. On their first visit, skin prick tests, with 29 common allergens including dust mites antigen, and sputum induction were performed. And 3 days later, methacholine challenge was done. 24 hours after methacholine challenge, treadmill test was performed and the positive EIB was defined as a 15% reduction or more in FEV1 from baseline after exercise. RESULTS: EIB was observed in 54 (40.9%) of 132 asthmatic subjects. There was no significant difference in atopy between EIB positive and EIB negative asthmatics. Eosinophil and eosinophil cationic protein in induced sputum were significantly higher in EIB positive asthmatics. We also found the significant correlation between bronchial responsiveness (BR) index and maximal % fall in FEV1. CONCLUSION: The severity of bronchospasm evoked by exercise was more closely related to eosinophilic airway inflammation and airway hyperresponsiveness to methacholine than atopy.