Temporal trends in antimicrobial consumption and an investigation of hospital antimicrobial stewardship activities through structured interviews

Objective: Although antimicrobial consumption data are routinely collected, linking these data to the actual antimicrobial stewardship program (ASP) remains challenging. The objective of the present study is to explore association between temporal trends in three categories of antimicrobial consumption and actually implemented of ASPs, in acute care hospitals through structured interviews. Design: Multicenter retrospective study with structured interviews. Setting: Japanese hospitals. Methods: Temporal trends in three antimicrobial consumption data including days of therapy (DOT) per 1,000 patient-days (PD), days of antibiotic spectrum coverage (DASC) per 1,000 PD, and DASC/DOT were collected from 10 hospitals between 2016 and 2024. Structured interviews to identify current ASP progression and challenges related to ASP promotion were conducted. Results: Ten hospitals participated in the study. Although all participating hospitals had implemented ASPs, most had introduced one or two core ASP interventions. The most commonly implemented ASP was post-prescription review and feedback for broad-spectrum antimicrobials. Despite the presence of ASPs, 50% of hospitals (5/10) demonstrated unfavorable changes in trends across all three metrics, characterized by increasing DASC, DOT, and DASC/DOT. Structured interviews identified various barriers to advancing ASP, including clinical pharmacist shortages, suboptimal infrastructure, limited financial or political support and insufficient knowledge and clinical experience related to ASP activities. Conclusions: The presence of ASPs in Japan did not consistently lead to changes in antimicrobial prescribing practices, as reflected in antimicrobial consumption metrics. Integrating longitudinal antimicrobial consumption data with structured qualitative assessments provides a more comprehensive understanding of ASP progression and promotion at the institutional level.