Background: Patients with acute asthma treated in the emergency department are frequently treated with inhaled beta-agonists and corticosteroids (CS) after discharge. The use of inhaled CS (ICS) following discharge may also be beneficial in acute asthma.
Objectives: To determine the effect of inhaled corticosteroids (ICS) on outcomes in the treatment of acute asthma following discharge from the emergency department (ED).
Search strategy: Randomised controlled trials (RCTs) were identified from the Cochrane Airways Review Group register which consists of systematic searches of EMBASE, MEDLINE and CINAHL databases supplemented by hand searching of 20 respiratory journals. In addition, abstracts from conferences were searched; primary authors and pharmaceutical companies were contacted to identify eligible studies. Bibliographies from included studies, known reviews, and texts also were searched.
Selection criteria: Only RCTs or quasi RCTs were eligible for inclusion. 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 (CS). Two reviewers independently assessed articles for potential relevance, final inclusion, and methodological quality - to "expand" the search. We didn't include any in the end)
Data collection and analysis: Data were extracted independently by two reviewers if the authors were unable to verify the validity of information. Several authors and pharmaceutical companies provided unpublished data. The data were analysed using the Cochrane Review Manager 4.0.4.
Main results: Ten trials were selected for inclusion. Three of these trials, involving a total of 909 patients, compared ICS plus CS Vs CS therapy alone. There was no demonstrated benefit of ICS therapy when used in addition to CS therapy in the trials. Relapses were reduced, but not significantly, with the addition of ICS therapy (OR: 0.68; 95% CI: 0.46 to 1.02). As well, no differences were demonstrated between the two groups for relapses requiring admission, quality of life, symptom scores, or adverse effects. Seven trials, involving a total of 1204 patients, compared high-dose ICS therapy alone Vs CS therapy alone after ED discharge. There were no significant differences demonstrated between ICS therapy alone and CS therapy alone for relapse rates (OR: 1.00; 95% CI: 0.66 to 1.52) or in the secondary outcomes of beta-agonist use, symptoms, or adverse events. However, the sample size was not adequate to confidently exclude the possibility of either treatment being significantly inferior, and severe asthmatics were excluded from these trials.
Reviewer's conclusions: There is insufficient evidence that ICS therapy provides additional benefit when used in combination with standard CS therapy upon ED discharge for acute asthma. There is some evidence that high-dose ICS therapy alone may be as effective as CS therapy when used in mild asthmatics upon ED discharge; however, there is a significant possibility of a type II error in drawing this conclusion. Further research is needed to clarify whether ICS therapy should be employed in acute asthma treatment in the ED or following ED discharge.