THE EFFECT OF AN INHALED CORTICOSTEROID (BUDESONIDE) ON EXERCISE-INDUCED ASTHMA IN CHILDREN

The effect of long-term treatment with inhaled corticosteroid on exercise-induced asthma (EIA) was studied in 55 children, aged 7-18 yrs (mean 12 yrs). We also compared the time course of stabilization of EIA to that of other indicators of airway responsiveness, such as peak expiratory flow (PEF) variation and the provocation dose of histamine causing a 20% fall in forced expiratory volume in one second (FEV1).All children participated in an ongoing multicentre study to compare the effects of long-term treatment either with the beta2-agonist salbutamol (600 mug.day-1) plus the inhaled corticosteroid budesonide (600 mug.day-1) (BA+CS), or salbutamol plus placebo (BA+PL), on airway calibre, airway responsiveness and symptoms. After a median follow-up of 22 months, the study design had to be changed, because of the high number of drop-outs on BA+PL. At that time, the treatment regimen of all children who had not withdrawn was changed into BA+CS. At the moment of change, and after 2 and 8 months of treatment, a treadmill exercise test was performed in two centres.Eighteen of the 22 children (82%) who were treated with BA+PL from the beginning had EIA, compared to 18 of the 33 children (55%) who were treated with BA-CS (pWe conclude that long-term treatment with inhaled corticosteroid reduced the prevalence of EIA by about 33% and the severity by about 50%, and, furthermore, that the various stimuli of airway hyperresponsiveness act through different bronchoconstricting mechanisms.