title: Exacerbations of chronic obstructive pulmonary disease: when are antibiotics indicated? A systematic review.
abstract: BACKGROUND
  For decades, there is an unresolved debate about adequate prescription of antibiotics for patients suffering from exacerbations of chronic obstructive pulmonary disease (COPD). The aim of this systematic review was to analyse randomised controlled trials investigating the clinical benefit of antibiotics for COPD exacerbations.
  
  
  METHODS
  We conducted a systematic review of randomised, placebo-controlled trials assessing the effects of antibiotics on clinically relevant outcomes in patients with an exacerbation. We searched bibliographic databases, scrutinized reference lists and conference proceedings and asked the pharmaceutical industry for unpublished data. We used fixed-effects models to pool results. The primary outcome was treatment failure of COPD exacerbation treatment.
  
  
  RESULTS
  We included 13 trials (1557 patients) of moderate to good quality. For the effects of antibiotics on treatment failure there was much heterogeneity across all trials (I(2) = 75%) [corrected] Meta-regression revealed severity of exacerbation as significant explanation for this heterogeneity (p = 0.038) [corrected] Antibiotics did not reduce treatment failures in outpatients with mild to moderate exacerbations (pooled odds ratio 1.81, 95% CI 0.55-1.18, I(2) = 13%) [corrected] Inpatients with severe exacerbations had a substantial benefit on treatment failure rates (pooled odds ratio of 0.25, 95% CI 0.16-0.39, I2 = 0%; number-needed to treat of 4, 95% CI 3-5) and on mortality (pooled odds ratio of 0.20, 95% CI 0.06-0.62, I2 = 0%; number-needed to treat of 14, 95% CI 12-30).
  
  
  CONCLUSIONS
  Antibiotics effectively reduce treatment failure and mortality rates in COPD patients with severe exacerbations. For patients with mild to moderate exacerbations, antibiotics may not be generally indicated and further research is needed to guide antibiotic prescription in these patients.
authors.affiliation: Horten Centre, University Hospital of Zurich, Postfach Nord, Zurich, Switzerland. milo.puhan@usz.ch
authors.forename: Milo A
authors.initials: MA
authors.lastname: Puhan
authors.forename: Daniela
authors.initials: D
authors.lastname: Vollenweider
authors.forename: Tsogyal
authors.initials: T
authors.lastname: Latshang
authors.forename: Johann
authors.initials: J
authors.lastname: Steurer
authors.forename: Claudia
authors.initials: C
authors.lastname: Steurer-Stey
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D006801:Humans; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy* / Q000401:mortality / Q000503:physiopathology*; D016032:Randomized Controlled Trials as Topic; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents