186. Factors associated with treatment mismatch and mortality in geriatric patients with bacteremia: A target for antimicrobial stewardship
Session: Poster Abstract Session: Antimicrobial Stewardship: Current State and Future Opportunities
Thursday, October 8, 2015
Room: Poster Hall
  • IDSA presentation 2015 10012015 final pdf.pdf (161.1 kB)
  • Background:

    Bacteremia results in substantial morbidity and mortality among geriatric patients. Japan is a rapidly aging society, however, little is known of the epidemiology of bacteremia in geriatric patients in Japanese institutions.


    We performed a retrospective cohort study of patients age >65 years old with bacteremia at a 790-bed, Japanese tertiary care hospital from January to December 2013. We defined treatment mismatch as either empiric antimicrobials not active against subsequently isolated organisms, or antimicrobial agents not administered before notification of positive cultures. Factors associated with a 30-day mortality of bacteremia in geriatric population were evaluated.      


    We identified 314 episodes of bacteremia in 279 patients; median age was 77 (range 65-94) and 166 (60%) were male.  Among 314 episodes of bacteremia, 132 (42%) were community-onset, 55 (18%) healthcare-associated community onset, and 127 (40%) hospital-onset. The most common sources of bacteremia were hepatobiliary (29%) and genitourinary tract (23%). Among the 314 bacteremia episodes, 97 (31%) had treatment mismatch [73 (75%) inappropriate empiric antimicrobial therapy; 24 (25%) no antimicrobials administered]. Treatment mismatch was associated with hospital-onset bacteremia [adjusted odds ratio (aOR) 3.52; 95%CI  1.78-6.94], and candidemia (aOR 8.69; 95% CI 1.87-40.38). Thirty-nine patients (14%) died <30 days after the first positive blood culture. Factors associated with a 30-day mortality were septic shock < 48 hours after first positive blood culture [adjusted hazard ratio (aHR) 5.25; 95%CI  2.16-12.76], Pitt bacteremia score > 3 (aHR 1.28; 95%CI 1.15-1.43), and no administration of antimicrobial agents (aHR 3.08; 95%CI 1.29-7.35)


    Treatment mismatch occurred in about one-third of geriatric Japanese patients with bacteremia. Not receiving empiric antimicrobial therapy was independently associated with 30-day mortality.

    Hitoshi Honda, MD, PhD1, Naofumi Higuchi, MD1, Kensuke Shintani, MD1, Masanori Higuchi, MD1, Yasuaki Tagashira, MD1 and David K. Warren, MD, MPH, FIDSA, FSHEA2, (1)Division of Infectious Diseases, Department of Medicine, Tokyo Metropolitan Tama General Medical Center, Tokyo, Japan, (2)Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO


    H. Honda, None

    N. Higuchi, None

    K. Shintani, None

    M. Higuchi, None

    Y. Tagashira, None

    D. K. Warren, None

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