Background: Smoking is as prevalent in asthmatics as in the general population. Asthmatic smokers benefit less from inhaled corticosteroids (ICS) than non-smoking asthmatics, possibly due to more smoking-induced small airways disease. Thus targeting small airways may be important in treating asthmatic (ex-) smokers. We hypothesized that extrafine particle ICS improve small airways function more than non-extrafine particle ICS in asthmatic (ex-) smokers. Methods: We performed an open-label, randomized, three-way cross-over study comparing extrafine beclomethasone (HFA-QVAR) to non-extrafine beclomethasone (HFA-Clenil) and fluticasone (HFA-Flixotide) in 22 smokers and 21 ex-smokers with asthma (>= 5 packyears).
Results: Improvement from baseline in PD20 adenosine after using QVAR, Clenil or Flixotide was 1.04 +/- 1.71, 1.09 +/- 2.12 and 0.94 +/- 1.97 doubling doses, mean +/- standard deviation (SD), respectively. The change from baseline in R-5-R-20 at PD20 adenosine after using QVAR, Clenil or Flixotide was -0.02 +/- 0.27, 0.02 +/- 0.21, and -0.02 +/- 0.31 kPa sL(-1), mean +/- SD, respectively. The change in PD20 adenosine and R5R20 at PD20 adenosine were neither statistically significant different between QVAR and Clenil (p = 0.86 and p = 0.82) nor between QVAR and Flixotide (p = 0.50 and p = 0.96).
Conclusion: Similar effectiveness in improving small airways function was found for extrafine and non-extrafine particle ICS treatment for asthmatic smokers and ex-smokers. (C) 2017 Elsevier Ltd. All rights reserved.