Background: Systemic corticosteroids therapy is central to the management of acute asthma The use of inhaled steroids may also be beneficial in this setting.

Objectives: To determine the benefit of ICS for the treatment of patients with acute asthma managed in the emergency department (ED).

Search strategy: Randomised controlled trials (RCTs) were identified from the Cochrane Airways Review Group register. Bibliographies from included studies, known reviews, and texts also were searched.

Selection criteria: Only RCTs or quasi-randomised trials were eligible for inclusion. Studies were included if patients presented with acute asthma to the ED or its equivalent, and were treated with ICS or placebo, in addition to standard therapy. Two reviewers independently selected potentially relevant articles, and then independently selected articles for inclusion. Methodological quality was independently assessed by two reviewers.

Data collection and analysis: Data were extracted independently by two reviewers if the authors were unable to verify the validity of extracted information. Missing data were obtained from the authors or calculated from other data presented in the paper.

Main results: Seven trials were selected for inclusion, but data were not available for one of them. In the six usable rials, (4 adult, 2 paediatric), a total of 352 patients were studied (179 ICS, 173 non-ICS treated). Patients treated with ICS were less likely to be admitted to hospital (OR: 0.30; 95% CI: 0.16, 0.57). This benefit was confined to patients not receiving concomitant systemic steroids. Such patients showed the same, but non-significant, trend towards reduced admissions compared to placebo treatment (OR 0.46; 95% CI: 0. 19, 1.11). In children, ICS appeared to be at least as effective as systemic steroids (OR 0.5; 95% CI: 0.24, 1.06). Patients receiving ICS demonstrated small, significant improvements in peak expiratory flows (PEFR WMD: 7%; 95% CI: 3, 13) and forced expiratory volumes (FEV-FEV1 WMD: 5.0%; 95% CI: 0.4, 9.7). The treatment was well tolerated, with few reported adverse side effects.

Reviewer's conclusions: Inhaled steroids reduced admission rates in patients with acute asthma who were not receiving concomitant systemic steroids. In children, inhaled steroids appear to be at least as effective as systemic steroids. Further research is needed to clarify the effect of ICS when used in addition to systemic corticosteroids, and to determine the optimal dose, agent, and frequency of ICS administration.