ABSTRACT
BACKGROUND: Antimicrobial stewardship programs (ASPs) are recommended in nursing homes (NHs), although data are limited. This study aimed to determine the clinical and ecological impact of an ASP for NHs. METHODS: We performed a cluster randomized controlled trial and a before-after study with interrupted time-series analyses in 14 NHs, for 30 consecutive months from July 2018 to December 2020, in Andalusia, Spain. Seven facilities implemented an ASP with a bundle of five educational measures (general-ASP) and 7 added one-to-one educational interviews (experimental-ASP). The primary outcome was the overall use of antimicrobials, calculated monthly, as defined daily doses (DDD) per 1000 residents-day (DRD). RESULTS: During the ASP implementation, the total mean antimicrobial consumption decreased by 31.2% (-16.72 DRD; p = 0.045) with respect to the pre-intervention period; the overall use of quinolones and amoxicillin-clavulanic acid dropped by 52.2% (p = 0.001) and 42.5% (p = 0.006) respectively; and the overall prevalence of MDRO decreased from 24.7% to 17.4% (p = 0.012). During the intervention period, 12.5 educational interviews per doctor were done in the experimental ASP-group; no differences were found in the total mean antimicrobial use between groups (-14.62 DRD; p = 0.25) and two unexpected SARS-CoV-2 waves affected the participating centers with significant increases in the overall mean use of total antimicrobials of 40% (51.56 DRD; p < 0.0001). CONCLUSION: This study suggests that an ASP for NHs appears to be associated with a decrease in total consumption of antimicrobials and prevalence of MDRO. This trial did not find benefits associated with educational interviews probably due to the COVID-19 pandemic.