Rationale: Asthma exacerbations are unpredictable, disruptive, and frightening, and are therefore important to prevent.
Objectives: We investigated whether a policy of quadrupling the dose of inhaled corticosteroid when asthma control starts to deteriorate reduces asthma exacerbations requiring treatment with oral corticosteroids.
Methods: A total of 403 people with asthma were given a self-management plan and randomized to take an active or placebo corticosteroid inhaler in addition to their usual asthma treatment when their PEF fell by 15% on 2 consecutive days or by 30% on 1 day. The study inhalers provided a quadrupling or no change in corticosteroid dose.
Measurements and main results: Eighteen of 197 (9%) and 29 of 203 (14%) participants had an exacerbation of asthma requiring treatment with oral corticosteroids in the active and placebo groups, respectively, giving a risk ratio of 0.64 (95% confidence interval, 0.37-1.11, P = 0.11). Of the 94 participants who started the study inhaler far fewer required treatment with oral corticosteroids in the active compared with the placebo group: 12 of 56 (21%) in the active group and 19 of 38 (50%) in the placebo group, giving a risk ratio of 0.43 (95% confidence interval, 0.24-0.78, P = 0.004).
Conclusions: Although our primary outcome did not reach statistical significance, quadrupling the dose of inhaled corticosteroid when asthma control starts to deteriorate appears to reduce acute exacerbations of asthma and deserves further investigation. Clinical trial registered with www.controlled-trials.com (ISRCTN 46018181).