title: Antibiotic therapy and 48-hour mortality for patients with pneumonia.
abstract: OBJECTIVE
  Although numerous articles have demonstrated that recommended empiric antimicrobial regimens are associated with decreased mortality at 30 days, there is controversy over whether appropriate antibiotic selection has a beneficial impact on mortality within the first 48 to 96 hours after admission. Our aim was to determine whether the use of guideline-concordant antibiotic therapy is associated with decreased mortality within the first 48 hours after admission for patients with pneumonia.
  
  
  METHODS
  A retrospective cohort study was conducted at two tertiary teaching hospitals in San Antonio, Texas. A propensity score was used to balance the covariates associated with the use of guideline-concordant antimicrobial therapy. A multivariable logistic regression model was used to assess the association between mortality within 48 hours and the use of guideline-concordant antibiotic therapy, after adjusting for potential confounders including the propensity score.
  
  
  RESULTS
  Information was obtained on 787 patients with community-acquired pneumonia. The median age was 60 years, 79% were male, and 20% were initially admitted to the intensive care unit. At presentation 52% of subjects were low risk, 34% were moderate risk, and 14% were high risk. Within the first 48 hours, 20 patients died. After adjustment for potential confounders, the use of guideline-concordant antimicrobial therapy (odds ratio 0.37, 95% confidence interval, 0.14-0.95) was significantly associated with decreased mortality at 48 hours after admission.
  
  
  CONCLUSIONS
  Using initial empiric guideline-concordant antimicrobial therapy is associated with decreased mortality at 48 hours. Further research needs to investigate methods to ensure that patients with community-acquired pneumonia are treated with appropriate antimicrobial therapies.
authors.affiliation: Veterans Evidence Based Research Dissemination and Implementation Center, South Texas Veterans Health Care System, San Antonio, Tex 78284, USA. mortensene@uthscsa.edu
authors.forename: Eric M
authors.initials: EM
authors.lastname: Mortensen
authors.forename: Marcos I
authors.initials: MI
authors.lastname: Restrepo
authors.forename: Antonio
authors.initials: A
authors.lastname: Anzueto
authors.forename: Jacqueline A
authors.initials: JA
authors.lastname: Pugh
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D015331:Cohort Studies; D017714:Community-Acquired Infections; D005260:Female; D019983:Guideline Adherence; D006801:Humans; D008297:Male; D008875:Middle Aged; D010343:Patient Admission / Q000706:statistics & numerical data; D011014:Pneumonia / Q000188:drug therapy* / Q000401:mortality*; D012189:Retrospective Studies; D020379:Risk Adjustment; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents