Simplified therapeutic guidelines: the main tool of antimicrobial stewardship programs associated with optimal antibiotic therapy.

Hospitals regularly seek to upgrade their antimicrobial stewardship program (ASP). Our aim was to evaluate the impact of simplified therapeutic guidelines (STGs) compared to various established tools for ASP on the rate of optimal antibiotic therapy (OAT) and antibiotic consumption. Audits of antibiotic prescriptions were carried out over a 24-month period. Feedback information led to STGs (e.g., ≤ 15 drugs). The impact of STGs was based on the rate of OAT, defined as a diagnosis of the infectious disease in the patient's medical records associated with the corresponding therapy indicated in the STGs or in other guidelines. STGs were compared to five other means of ASP: internal or national guidelines, audit, information regarding antibiotic consumption and bacterial resistance, and restricted access to targeted antibiotics. Antibiotic consumption was measured in defined daily doses/1000 days of hospital stay, focusing on third-generation cephalosporins (TGC) and fluoroquinolones (FQ). Twenty-six hospitals were audited from April 2017 to June 2019. A total of 1,028 antibiotic prescriptions were analyzed, including 204 (20%) after STG implementation in seven hospitals. In multivariate analysis, OAT (n = 176, 17%) was associated with STGs, AOR 2.21 [1.51-3.22], and with three tools in place, 1.75 [1.24-2.48]. The relative variations of consumption of TGC and FQ for hospitals with or without STGs were - 13.1 vs. + 9.4% and - 18.5 vs. - 2.7%, respectively, from 2018 to 2019. STGs were more likely than other ASP tools to improve the rate of OAT and to reduce the consumption of antibiotics.