title: Statins Reduce Mortality After Non-severe but Not After Severe Pneumonia: A Systematic Review and Meta-Analysis.
abstract: OBJECTIVE
  The objective of this study was to perform a systematic review and meta-analysis of the effects of statins on mortality for patients with non-severe pneumonia or severe pneumonia.
  
  
  METHODS
  PubMed, EMBASE, Cochrane Database of Systematic Reviews, Cochrane central register of controlled trials and Clinicaltrials.gov were searched for the association between statins and non-severe/severe pneumonia. Eligible articles were analyzed in Stata 12.0.
  
  
  RESULTS
  The database search yielded a total of 566 potential publications, 24 studies involving 312,309 patients met the eligibility criteria. Pooled unadjusted data showed that statin use was associated with lower mortality after non-severe pneumonia (odds ratio [OR] 0.70, 95% confidence interval [CI], 0.66-0.73), but not severe pneumonia (OR 1.05; 95% CI, 0.86-1.28). However, this protective effect of statins was weakened using adjusted estimates (OR 0.78, 95% CI, 0.75-0.82). Besides, protective effect of statins was attenuated by confounders in a subgroup analysis, especially when accounting for pneumonia severity indicators (OR 0.88; 95% CI, 0.80-0.96).
  
  
  CONCLUSIONS
  Statin use was associated with reduced mortality after non-severe pneumonia but not severe pneumonia and this protective effect was weakened in subgroups.
authors.affiliation: Southern Medical University, Guangzhou, Guangdong Province, P. R. China; Department of Respiratory Medicine，Liuhuaqiao Hospital, Guangzhou, Guangdong Province, China; Department of Intensive Care Unit, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong Province, P. R. China.
authors.forename: Mingwang
authors.initials: M
authors.lastname: Jia
authors.forename: Wenjie
authors.initials: W
authors.lastname: Huang
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Zhong
authors.initials: Z
authors.lastname: Xu
authors.forename: Lichan
authors.initials: L
authors.lastname: Wu
mesh_terms: D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use*; D009026:Mortality / Q000639:trends; D064887:Observational Studies as Topic / Q000379:methods; D011014:Pneumonia / Q000175:diagnosis / Q000188:drug therapy* / Q000401:mortality*; D012720:Severity of Illness Index
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors