title: Beneficial effects of statins on outcomes in pneumonia: a systematic review and meta-analysis.
abstract: OBJECTIVE
  There exist reports that statin treatment has beneficial effects for patients with pneumonia. The objective of this study was to evaluate whether the available published data support that statins as adjunctive therapy could reduce mortality associated with pneumonia and, thus, help to assess whether a randomized controlled study is warranted.
  
  
  METHODS
  A meta-analysis of observational studies such as cohort studies and case-control studies identified in Pubmed, Scopus, EMBASE, the Cochrane Central Register of Controlled Trials and Clinicaltrials.gov. Eligible patients were adults with pneumonia. Studies that reported mortality of pneumonia grouped by statins usage were included. Data was analyzed and pooled using Revman 5.1.
  
  
  RESULTS
  Fourteen studies with 269,739 participants were included in this study. Pooled analysis showed that statin treatment was associated with lower 30-day mortality, with an OR of 0.44 (95% CI, 0.29-0.67), and an adjusted OR of 0.59 (95% CI 0.48-0.73, NNT30d = 19). Statin therapy was also associated with lower long-term (> 30 days) mortality, with an OR of 0.49 (95% CI, 0.29-0.84) and an adjusted OR of 0.65 (95% CI, 0.51-0.82, NNTlong-term = 15). For pneumonia inpatients, the raw data demonstrated no significant benefit from statin therapy (OR = 0.86, 95% CI, 0.56-1.34). Adjusted data showed a marginal benefit (adjusted OR = 0.89, 95% CI, 0.81-0.97, NNTinpatient = 230). Subgroup analysis revealed that current statin users might have better outcomes than recent or past statins users.
  
  
  CONCLUSIONS
  This meta-analysis supports that patients who happen to be receiving statin therapy have less mortality from pneumonia. However, it remains unclear whether initiation of statins at time of diagnosis is beneficial. There is only modest evidence to support the value of a well-designed randomized controlled clinical trial.
authors.affiliation: Department of SICU, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China. shanpingj_sys@126.com.
authors.forename: H-H
authors.initials: HH
authors.lastname: Cheng
authors.forename: T-T
authors.initials: TT
authors.lastname: Tang
authors.forename: Q
authors.initials: Q
authors.lastname: He
authors.forename: L-J
authors.initials: LJ
authors.lastname: Huang
authors.forename: X-L
authors.initials: XL
authors.lastname: Lin
authors.forename: M
authors.initials: M
authors.lastname: Chen
authors.forename: C
authors.initials: C
authors.lastname: Yang
authors.forename: D-F
authors.initials: DF
authors.lastname: Geng
authors.forename: S-P
authors.initials: SP
authors.lastname: Jiang
mesh_terms: D015982:Bias; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use*; D016017:Odds Ratio; D011014:Pneumonia / Q000188:drug therapy* / Q000453:epidemiology
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors