title: Associations between initial antimicrobial therapy and medical outcomes for hospitalized elderly patients with pneumonia.
abstract: BACKGROUND
  Although medical practice guidelines exist, there have been no large-scale studies assessing the relationship between initial antimicrobial therapy and medical outcomes for patients hospitalized with pneumonia.
  
  
  OBJECTIVE
  To determine the associations between initial antimicrobial therapy and 30-day mortality for these patients.
  
  
  METHODS
  Hospital records for 12945 Medicare inpatients (> or = 65 years of age) with pneumonia were reviewed. Associations between initial antimicrobial regimens and 30-day mortality were assessed with Cox proportional hazards models, adjusting for baseline differences in patient characteristics, illness severity, and processes of care. Comparisons were made with patients treated with a non-pseudomonal third-generation cephalosporin alone (the reference group).
  
  
  RESULTS
  Initial treatment with a second-generation cephalosporin plus macrolide (hazard ratio [HR], 0.71; 95% confidence interval [CI], 0.52-0.96), a non-pseudomonal third-generation cephalosporin plus macrolide (HR, 0.74; 95% CI, 0.60-0.92), or a fluoroquinolone alone (HR, 0.64; 95% CI, 0.43-0.94) was independently associated with lower 30-day mortality. Adjusted mortality among patients initially treated with these 3 regimens became significantly lower than that in the reference group beginning 2, 3, and 7 days, respectively, after hospital admission. Use of a beta-lactam/beta-lactamase inhibitor plus macrolide (HR, 1.77; 95% CI, 1.28-2.46) and an aminoglycoside plus another agent (HR, 1.21; 95% CI, 1.02-1.43) were associated with an increased 30-day mortality.
  
  
  CONCLUSIONS
  In this study of primarily community-dwelling elderly patients hospitalized with pneumonia, 3 initial empiric antimicrobial regimens were independently associated with a lower 30-day mortality. The more widespread use of these antimicrobial regimens is likely to improve the medical outcomes for elderly patients with pneumonia.
authors.affiliation: Department of Pharmaceutical Care and Health Systems, College of Pharmacy, University of Minnesota, Minneapolis, USA.
authors.forename: P P
authors.initials: PP
authors.lastname: Gleason
authors.forename: T P
authors.initials: TP
authors.lastname: Meehan
authors.forename: J M
authors.initials: JM
authors.lastname: Fine
authors.forename: D H
authors.initials: DH
authors.lastname: Galusha
authors.forename: M J
authors.initials: MJ
authors.lastname: Fine
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents / Q000627:therapeutic use*; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination / Q000627:therapeutic use*; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D018410:Pneumonia, Bacterial / Q000188:drug therapy* / Q000401:mortality*; D016016:Proportional Hazards Models; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents