Meta-analysis of increased dose of inhaled steroid or addition of salmeterol in symptomatic asthma (MIASMA)

Abstract Objective: To examine the benefits of adding salmeterol compared with increasing dose of inhaled corticosteroids. Design: Systematic review of randomised, double blind clinical trials. Independent data extraction and validation with summary data from study reports and manuscripts. Fixed and random effects analyses. Setting: EMBASE, Medline, and GlaxoWellcome internal clinical study registers. Main outcome measures: Efficacy and exacerbations. Results: Among 2055 trials of treatment with salmeterol, there were nine parallel group trials of ≥12 weeks with 3685 symptomatic patients aged ≥12 years taking inhaled steroid in primary or secondary care. Compared with response to increased steroids, in patients receiving salmeterol morning peak expiratory flow was greater at three months (difference 22.4 (95% confidence interval 15.0 to 30.0) litre/min, P