title: Effect of long-acting beta-agonists on the frequency of COPD exacerbations: a meta-analysis.
abstract: OBJECTIVE
  Inhaled long-acting beta-agonists have been licensed for the treatment of chronic obstructive pulmonary disease (COPD) since the late 1990s, and they improve lung function and symptoms of dyspnoea. However, the evidence that long-acting beta-agonists alone can reduce the rate of COPD exacerbations is not conclusive. This meta-analysis was performed to evaluate their effect on the frequency of exacerbations.
  
  
  METHODS
  MEDLINE, EMBASE, CINAHL and the Cochrane trials database were searched for the review. Randomized controlled trials of greater than or equal to 24weeks' treatment duration comparing long-acting beta-agonists (LABAs) with placebo were reviewed. Studies were pooled to yield odds ratios (ORs) with 95% confidence intervals (CIs).
  
  
  CONCLUSIONS
  Seventeen randomized controlled trials (11871 randomized subjects) met the inclusion criteria and were selected for analysis. Salmeterol, formoterol and indacaterol significantly reduced COPD exacerbations compared with placebo. Salmeterol significantly reduced COPD exacerbations with both study arms exposed or not exposed to inhaled corticosteroids (ICS). The summary ORs were 0·79 (95% CI: 0·67-0·92; P<0·01) and 0·80 (95% CI: 0·65-0·99; P=0·04), respectively. However, when both arms were not exposed to ICS, there was no significant reduction in exacerbations with formoterol compared with placebo. The 'summary OR was 0·93 (95% CI: 0·75-1·15; P=0·50).
  
  
  CONCLUSIONS
  Long-acting beta-agonists reduce the frequency of COPD exacerbations. Salmeterol, formoterol and indacaterol significantly reduced COPD exacerbations compared with placebo. Salmeterol but not formoterol decreased exacerbations significantly in the absence of ICS.
authors: Department of Respiratory Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. wangjianmiao2010@126.com
authors: J
authors: J
authors: Wang
authors: B
authors: B
authors: Nie
authors: W
authors: W
authors: Xiong
authors: Y
authors: Y
authors: Xu
mesh_terms: D000280:Administration, Inhalation; D058666:Adrenergic beta-2 Receptor Agonists / Q000008:administration & dosage / Q000627:therapeutic use*; D000420:Albuterol / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000627:therapeutic use; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D003692:Delayed-Action Preparations; D004359:Drug Therapy, Combination; D004983:Ethanolamines / Q000008:administration & dosage / Q000627:therapeutic use; D000068759:Formoterol Fumarate; D005938:Glucocorticoids / Q000008:administration & dosage / Q000627:therapeutic use; D006801:Humans; D007189:Indans / Q000008:administration & dosage / Q000627:therapeutic use; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy* / Q000503:physiopathology; D015363:Quinolones / Q000008:administration & dosage / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic; D000068299:Salmeterol Xinafoate
chemical_list: D058666:Adrenergic beta-2 Receptor Agonists; D001993:Bronchodilator Agents; D003692:Delayed-Action Preparations; D004983:Ethanolamines; D005938:Glucocorticoids; D007189:Indans; D015363:Quinolones; D000068299:Salmeterol Xinafoate; C510790:indacaterol; D000420:Albuterol; D000068759:Formoterol Fumarate