Background: Inhaled corticosteroids (ICS) are the mainstay of asthma treatment, but conventional ICS may have limited effectiveness in inflammation and patency of small airways. Ciclesonide is delivered and deposited in the peripheral region of the lung as a small particle corticosteroid. The aim of the study is to compare the effects of ciclesonide with fluticasone propionate on small airway function in asthma.
Methods: Thirty mild persistent asthma patients treated with 200 microg of fluticasone propionate were randomized to receive either ciclesonide 200 microg once daily or fluticasone propionate 100 microg twice daily for 8 weeks. Small airway function was assessed by impulse oscillometry (IOS) and percentage of eosinophil induced sputum.
Results: We observed that ciclesonide significantly improved IOS measured resistance of small airways (R5-R20; p<0.05), distal reactance (X5; p<0.01), reactance area (AX; p<0.01), and decreased late-phase sputum eosinophil level (p<0.01) compared with fluticasone propionate. There were no significant changes in spirometry indices in either group during the study.
Conclusions: These findings suggest that ciclesonide improves small airway function and inflammation compared with fluticasone propionate in mild asthma. This study provides evidence that IOS and late-phase induced sputum allows detection of changes in the small airways that can not be detected by spirometry.