304. Impact of Using Guideline-Concordant Antibiotics in 3203 Patients Hospitalized with Pneumonia: Prospective Cohort Study
Session: Poster Abstract Session: Antimicrobial Therapy: Clinical Studies
Friday, October 21, 2011
Room: Poster Hall B1
  • 304_LeylaAsadi(2).pdf (790.2 kB)
  • Background: For patients hospitalized with pneumonia, guidelines recommend empiric antibiotics covering both typical and atypical pathogens and some suggest that macrolide/b-lactam combinations are preferable. We hypothesized that guideline-concordant antibiotic regimens in general, and macrolide/b-lactam combinations specifically, would reduce morbidity and mortality.

    Methods: All patients hospitalized with pneumonia in Edmonton, Alberta, Canada were managed according to a clinical pathway and enrolled in a population-based registry. Clinical data, Pneumonia Severity Index (PSI) and treatments were collected. Guideline-concordant regimens were respiratory fluoroquinolones or macrolide/b-lactams; all other regimens were discordant. The main outcome was the composite of in-hospital mortality or intensive care unit (ICU) admission. 

    Results: The study included 3203 patients; mean age 69 years, 52% female, most had severe pneumonia (63% PSI Class IV-V). Overall, 321 (10%) patients died, 306 (10%) were admitted to ICU and 570 (18%) achieved the composite of death or ICU admission. Most (2884 [90%]) patients received guideline-concordant antibiotics. Receipt of guideline-concordant antibiotics was independently associated with decreased death or ICU admission (131[41%] vs 439[15%], adjusted odds ratio [aOR] 0.25, 95%CI 0.19-0.33, p<0.001), although reductions in mortality alone (15% vs 9%, aOR 0.78, 95%CI0.53-1.12, p=0.17) were not statistically significant.  Within the guideline-concordant subgroup (n=2702), macrolide/b-lactam combinations were not significantly associated with better outcomes than respiratory fluoroquinolones for either the composite endpoint (17% vs 15%) or death alone (8% vs 10%). 

    Conclusion: In our study, guideline-concordant antibiotic regimens were associated with better outcomes for patients hospitalized with pneumonia. Our findings do not; however, support any advantage to using macrolide/b-lactam combinations.

    Subject Category: C. Clinical studies of bacterial infections and antibacterials including sexually transmitted diseases and mycobacterial infections (surveys, epidemiology, and clinical trials)

    Leyla Asadi, MD1, Dean T. Eurich, PhD2, John-Michael Gamble, MSc2, Jasjeet K. Minhas, MSc2, Thomas Marrie, MD3 and Sumit R. Majumdar, MD, MPH4, (1)Medicine, University of Alberta, Edmonton, AB, Canada, (2)School of Public Health, University of Alberta, Edmonton, AB, Canada, (3)Medicine, Dalhousie University, Nova Scotia, NS, Canada, (4)Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada


    L. Asadi, None

    D. T. Eurich, None

    J. M. Gamble, None

    J. K. Minhas, None

    T. Marrie, None

    S. R. Majumdar, None

    Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.