Background

Patients with acute asthma treated in the emergency department (ED) are frequently treated with inhaled beta₂‐agonists and systemic corticosteroids after discharge. The use of inhaled corticosteroids (ICS) following discharge may also be beneficial in improving patient outcomes after acute asthma.

Objectives

To determine the effectiveness of ICS on outcomes in the treatment of acute asthma following discharge from the ED. To quantify the effectiveness of ICS therapy on acute asthma following ED discharge, when used in addition to, or as a substitute for, systemic corticosteroids.

Search methods

Controlled clinical trials (CCTs) were identified from the Cochrane Airways Review Group register, which consists of systematic searches of EMBASE, MEDLINE and CINAHL databases supplemented by handsearching of respiratory journals and conference proceedings. In addition, primary authors and pharmaceutical companies were contacted to identify eligible studies. Bibliographies from included studies, known reviews and texts also were searched. The searches have been conducted up to September 2012

Selection criteria

We included both randomised controlled trials (RCTs) and quasi‐RCTs. Studies were included if patients were treated for acute asthma in the ED or its equivalent, and following ED discharge were treated with ICS therapy either in addition to, or as a substitute for, oral corticosteroids. Two review authors independently assessed articles for potential relevance, final inclusion and methodological quality.

Data collection and analysis

Data were extracted independently by two review authors, or confirmed by the study authors. Several authors and pharmaceutical companies provided unpublished data. The data were analysed using the Cochrane Review Manager software. Where appropriate, individual and pooled dichotomous outcomes were reported as odds ratios (OR) or relative risks (RR) with 95% confidence intervals (CIs). Where appropriate, individual and pooled continuous outcomes were reported as mean differences (MD) or standardized mean differences (SMD) with 95% CIs. The primary analysis employed a fixed effect model and heterogeneity is reported using I‐squared (I²) statistics.

Main results

Twelve trials were eligible for inclusion. Three of these trials, involving a total of 909 patients, compared ICS plus systemic corticosteroids versus oral corticosteroid therapy alone. There was no demonstrated benefit of ICS therapy when used in addition to oral corticosteroid therapy in the trials. Relapses were reduced; however, this was not statistically significant with the addition of ICS therapy (OR 0.68; 95% CI 0.46 to 1.02; 3 studies; N = 909). In addition, no statistically significant differences were demonstrated between the two groups for relapses requiring admission, quality of life, symptom scores or adverse effects.

Nine trials, involving a total of 1296 patients compared high‐dose ICS therapy alone versus oral corticosteroid therapy alone after ED discharge. There were no significant differences demonstrated between ICS therapy alone versus oral corticosteroid therapy alone for relapse rates (OR 1.00; 95% CI 0.66 to 1.52; 4 studies; N = 684), admissions to hospital, or in the secondary outcomes of beta₂‐agonist use, symptoms or adverse events. However, the sample size was not adequate to exclude the possibility of either treatment being significantly inferior and people with severe asthma were excluded from these trials.

Authors' conclusions

There is insufficient evidence that ICS therapy provides additional benefit when used in combination with standard systemic corticosteroid therapy upon ED discharge for acute asthma. There is some evidence that high‐dose ICS therapy alone may be as effective as oral corticosteroid therapy when used in mild asthmatics upon ED discharge; however, the confidence intervals were too wide to be confident of equal effectiveness. Further research is needed to clarify whether ICS therapy should be employed in acute asthma treatment following ED discharge. The review does not suggest any reason to stop usual treatment with ICS following ED discharge, even if a course of oral corticosteroids are prescribed.