title: Attributable mortality of ventilator-associated pneumonia: a meta-analysis.
abstract: OBJECTIVE
  To investigate whether ventilator-associated pneumonia (VAP) is a true cause of mortality in the intensive care unit setting.
  
  
  METHODS
  We performed a meta-analysis of available data without time restrictions. A conservative random effects model was employed to calculate  pooled odds ratios (ORs) and 95% confidence intervals (CIs).
  
  
  RESULTS
  Of 968 retrieved reports, 44 studies fulfilled our inclusion criteria. Presence, as opposed to absence, of VAP was associated with higher mortality in the ICU setting (OR 1.96, 95%CI 1.26-3.04). This result persisted  when matched case-control studies (OR 1.73, 95%CI 1.23-2.45) or studies in which VAP was microbiologically confirmed in all patients (OR 2.20, 95%CI 1.01-4.81) were evaluated separately. VAP continued to be associated with higher mortality when the impact of immune suppression  was controlled. VAP was not associated with higher mortality in the subgroup analysis of studies including patients who received appropriate initial antimicrobial treatment (OR 1.64, 95%CI 0.68-3.96).
  
  
  CONCLUSIONS
  Presence, compared to absence, of VAP seems to be associated with higher  mortality in critically ill patients. Appropriateness of initial antimicrobial treatment in such patients may moderate this association.
authors.affiliation: Alfa Institute of Biomedical Sciences, Athens, Greece.
authors.forename: M
authors.initials: M
authors.lastname: Agrafiotis
authors.forename: I I
authors.initials: II
authors.lastname: Siempos
authors.forename: T K
authors.initials: TK
authors.lastname: Ntaidou
authors.forename: M E
authors.initials: ME
authors.lastname: Falagas
mesh_terms: D000890:Anti-Infective Agents / Q000627:therapeutic use*; D016638:Critical Illness; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data*; D015233:Models, Statistical; D053717:Pneumonia, Ventilator-Associated / Q000188:drug therapy / Q000382:microbiology / Q000401:mortality*; D012107:Research Design
chemical_list: D000890:Anti-Infective Agents