title: Effect of ciclesonide dose and duration of therapy on exercise-induced bronchoconstriction in patients with asthma.
abstract: BACKGROUND
  Inhaled corticosteroid therapy improves exercise symptoms in asthmatic subjects.
  
  
  OBJECTIVE
  We sought to evaluate exercise-induced bronchoconstriction (EIB) as a method of determining the dose and time responses of inhaled corticosteroid therapy.
  
  
  METHODS
  In this double-blind, randomized, cross-over study with 2 parallel arms, 4 doses of inhaled ciclesonide (40 microg and 160 microg or 80 microg and 320 microg) were compared over 3 weeks of treatment. Twenty-six asthmatic subjects (age range, 14-27 years) with baseline FEV1 values of greater than 70% of predicted value were enrolled. The primary outcome was the maximum percentage decrease in FEV1 after standardized exercise challenge.
  
  
  RESULTS
  After 1 week of therapy, the mean +/- SEM reduction in maximum decrease in FEV1 in the ciclesonide 40-microg/80-microg dose group was 9% +/- 2.6% (95% CI, 3.9% to 14%), with no additional reduction thereafter. In the ciclesonide 160-microg/320-microg dose group, there was an 8.7% +/- 2.5% (95% CI, 3.7% to 13.7%) reduction in maximum decrease in FEV1 after week 1, which continued in a linear fashion during subsequent weeks of treatment. No difference was found between the 2 treatment arms in the temporal response of EIB to ciclesonide treatment. The maximum percentage attenuation in EIB achieved was 51.1% +/- 7.9%, which was achieved by using the 320-microg dose after 3 weeks of treatment.
  
  
  CONCLUSIONS
  A significant improvement in EIB was demonstrated for all doses of ciclesonide. Use of 160 microg/320 microg of ciclesonide resulted in a continuing improvement in FEV1 with time, and no plateau was seen in protective effect during 3 weeks of treatment.
  
  
  CONCLUSIONS
  Attenuation in exercise-induced decrease can be seen as early as after 1 week of therapy with inhaled ciclesonide at doses greater than 40 microg. However, maximal attenuation in exercise response continues to increase at doses greater than or equal to 200 microg, even after 3 weeks of therapy.
authors: Hospital for Sick Children, University of Toronto, Ontario, Canada. padmaja.subbarao@sickkids.ca
authors: Padmaja
authors: P
authors: Subbarao
authors: Mylinh
authors: M
authors: Duong
authors: Ellinor
authors: E
authors: Adelroth
authors: Joceline
authors: J
authors: Otis
authors: George
authors: G
authors: Obminski
authors: Mark
authors: M
authors: Inman
authors: Soren
authors: S
authors: Pedersen
authors: Paul M
authors: PM
authors: O'byrne