title: Comparative effectiveness of long term drug treatment strategies to prevent asthma exacerbations: network meta-analysis.
abstract: OBJECTIVE
  To determine the comparative effectiveness and safety of current maintenance strategies in preventing exacerbations of asthma.
  
  
  METHODS
  Systematic review and network meta-analysis using Bayesian statistics.
  
  
  METHODS
  Cochrane systematic reviews on chronic asthma, complemented by an updated search when appropriate. ELIGIBILITY CRITERIA TRIALS OF Adults with asthma randomised to maintenance treatments of at least 24 weeks duration and that reported on asthma exacerbations in full text. Low dose inhaled corticosteroid treatment was the comparator strategy. The primary effectiveness outcome was the rate of severe exacerbations. The secondary outcome was the composite of moderate or severe exacerbations. The rate of withdrawal was analysed as a safety outcome.
  
  
  RESULTS
  64 trials with 59,622 patient years of follow-up comparing 15 strategies and placebo were included. For prevention of severe exacerbations, combined inhaled corticosteroids and long acting β agonists as maintenance and reliever treatment and combined inhaled corticosteroids and long acting β agonists in a fixed daily dose performed equally well and were ranked first for effectiveness. The rate ratios compared with low dose inhaled corticosteroids were 0.44 (95% credible interval 0.29 to 0.66) and 0.51 (0.35 to 0.77), respectively. Other combined strategies were not superior to inhaled corticosteroids and all single drug treatments were inferior to single low dose inhaled corticosteroids. Safety was best for conventional best (guideline based) practice and combined maintenance and reliever therapy.
  
  
  CONCLUSIONS
  Strategies with combined inhaled corticosteroids and long acting β agonists are most effective and safe in preventing severe exacerbations of asthma, although some heterogeneity was observed in this network meta-analysis of full text reports.
authors.affiliation: Department of General Practice, Academic Medical Center, University of Amsterdam, PO box 22700, 1105 DE, Amsterdam, Netherlands r.j.loijmans@amc.nl.
authors.forename: Rik J B
authors.initials: RJ
authors.lastname: Loymans
authors.affiliation: Division of Clinical Epidemiology and Biostatistics, Institute of Social and Preventive Medicine, University of Bern, Berne, Switzerland Department of Health Sciences and Health Policy, University of Lucerne, Lucerne, Switzerland Swiss Paraplegic Research, Nottwil, Switzerland.
authors.forename: Armin
authors.initials: A
authors.lastname: Gemperli
authors.affiliation: Department of General Practice, Academic Medical Center, University of Amsterdam, PO box 22700, 1105 DE, Amsterdam, Netherlands.
authors.forename: Judith
authors.initials: J
authors.lastname: Cohen
authors.affiliation: Department of Health Sciences, Section Health Economics and Health Technology Assessment, VU University Amsterdam, Amsterdam, Netherlands.
authors.forename: Sidney M
authors.initials: SM
authors.lastname: Rubinstein
authors.affiliation: Department of Respiratory Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Sterk
authors.affiliation: Clinical Management Group, Woolcock Institute of Medical Research, University of Sydney, Sydney, NSW, Australia.
authors.forename: Helen K
authors.initials: HK
authors.lastname: Reddel
authors.affiliation: Division of Clinical Epidemiology and Biostatistics, Institute of Social and Preventive Medicine, University of Bern, Berne, Switzerland.
authors.forename: Peter
authors.initials: P
authors.lastname: Jüni
authors.affiliation: Department of General Practice, Academic Medical Center, University of Amsterdam, PO box 22700, 1105 DE, Amsterdam, Netherlands.
authors.forename: Gerben
authors.initials: G
authors.lastname: ter Riet
mesh_terms: D000280:Administration, Inhalation; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000009:adverse effects; D000318:Adrenergic beta-Agonists / Q000008:administration & dosage; D000328:Adult; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D001249:Asthma / Q000517:prevention & control*; D002908:Chronic Disease; D057186:Comparative Effectiveness Research; D006801:Humans; D008134:Long-Term Care; D009330:Nebulizers and Vaporizers; D016032:Randomized Controlled Trials as Topic; D015983:Selection Bias
chemical_list: D000305:Adrenal Cortex Hormones; D000318:Adrenergic beta-Agonists; D018927:Anti-Asthmatic Agents