Comparing the effects of antimicrobial stewardship at primary emergency centers

Antimicrobial prescription rates tend to be high in outpatient settings and Primary Emergency Medical Centers (PECs) in Japan encounter difficulties in implementing antimicrobial stewardship programs (ASPs). While a nudge-based ASP publishing monthly newsletters reduces inappropriate prescription of oral third-generation cephalosporins (3GCs), which requires considerable effort. Therefore, developing more preferable ASP models in PECs is essential.

We conducted a three-center, retrospective observational study. Himeji City Emergency Medical Center (Site A) introduced a facility-specific guideline for antimicrobial stewardship with reference to national guidelines. The Kobe Children's Primary Emergency Medical Center (Site B) provided the results of monitoring antibiotics prescription in a monthly newsletter. The Hanshin-Kita Children's First-Aid Center (Site C) did not perform a specific ASP. Prescription rates for 3GCs were categorized into pre- and post-intervention and compared using Poisson regression analysis. The difference-in-difference method was used to assess the effect of these interventions.

The numbers of patients pre- and post- intervention were 177,126 and 91,251, respectively. The 3GCs prescription rate at Site A, Site B, and Site C decreased from 6.7%, 4.2%, and 6.1% in 2016 to 2.3%, 1.0%, and 2.0% in 2019, respectively. Site B had a greater reduction than Site A and Site C (relative risk [RR] 0.71 [95% confidence interval (CI): 0.62-0.82]; p < 0.001, RR 0.71, [95% CI: 0.62-0.81]; p < 0.001). There was no significant difference between Site A and Site C (RR 1.00 [95% CI 0.88-1.13]; p = 0.963).

A facility-specific guideline was less effective than a nudge-based ASP for decreasing oral 3GC prescriptions in PECs.