Original Research
Saturday, November 11, 2023
11:30 AM–01:00 PM
Abstract
Introduction: Antibiotic de-escalation is a commonly used strategy that attempts to balance the need for early administration of appropriate antibiotics while reducing the risk of resistance development by narrowing the spectrum of antibiotics. However, the clinical evidence assessing its impact is limited.
Research Question or Hypothesis: De-escalation using a novel beta-lactam spectrum score (BLSS) approach is associated with a decreased risk of new resistance in critically ill patients.
Study Design: Single-center retrospective cohort study.
Methods: Adult patients with severe sepsis or septic shock from an academic medical center were enrolled between 2010 and 2017. BLSS were captured using the antimicrobial spectrum index method and BLSS of = 7 for two consecutive days denoted cohort entry. Patients were grouped into three categories: 1) de-escalation, 2) no change, or 3) escalation, using the novel cumulative BLSS during follow-up to 60 days. Primary outcome was the isolation of a new drug-resistant Gram-negative bacteria from a clinical culture. A time-dependent Cox proportional hazards model with death as a competing risk was utilized, adjusted for multiple covariates.
Results: 7,748 patients were included, with 1,579, 4,805, and 1,364 included in the de-escalation, no change, and escalation groups, respectively. The overall rate of new resistance was 8.3%, with 7.2%, 8.9%, and 7.8% in the de-escalation, no change, and escalation groups, respectively. The hazard ratio of developing new Gram-negative resistance with de-escalation vs. no-change: 0.684 (95% CI: 0.547 to 0.855); de-escalation vs. no change + escalation: 0.861 (95% CI: 0.750 to 0.988); de-escalation vs. escalation: 1.251 (95% CI: 0.901, 1.738).
Conclusion: De-escalation was associated with a decreased risk of new resistance development compared to no change and/or escalation. This represents the largest study to date showing the utility of de-escalation in the prevention of antimicrobial resistance.
Presenting Author
Joel Arackal PharmDUniversity of Health Sciences and Pharmacy in St. Louis
Authors
Jaylana Ahmetspahic Student
University of Health Sciences and Pharmacy
Marin Kollef MD
Barnes-Jewish Hospital and Washington University School of Medicine
Nicholas Hampton PharmD
Barnes-Jewish Hospital
Scott Micek PharmD
St. Louis College of Pharmacy at University of Health Sciences and Pharmacy in St. Louis
Taehwan Park PhD
St. Johns Univeristy
Besu Teshome PharmD, MSc
St. Louis College of Pharmacy at University of Health Sciences and Pharmacy in St. Louis