Antimicrobial Use in U.S. Hospitals: Comparison of 2015 and 2023 Prevalence Surveys

Background Prevalence surveys in U.S. hospitals in 2011 and 2015 showed that half of inpatients received antimicrobials on the survey day or day before. We repeated the survey in 2023 to assess changes in antimicrobial use (AU). Methods Ten Emerging Infections Program (EIP) sites recruited up to 25 hospitals each, prioritizing prior participants. EIP staff reviewed medical records of randomly selected inpatients from the survey day morning census and documented AU on the survey day or day before. We compared AU and stewardship characteristics between 2023 and 2015 and used multivariable log-binomial regression to identify factors associated with AU in 2023. Results Antimicrobial stewardship programs were present in 215/218 hospitals in 2023 (98.6%) compared with 158/199 (79.4%) in 2015. Of 13 653 patients in 2023, 6785 (49.7%) received ≥1 antimicrobial on the survey day or day before. Among 151 hospitals participating in both surveys, overall AU prevalence was similar in 2015 and 2023 (49.2% vs 49.1%), with decreases in neonatal critical care (23.4% to 17.1%) and increases in mother–baby units (24.4% to 32.8%). Fluoroquinolone use declined (9.2% to 2.8%), while third- or fourth-generation cephalosporin use increased (12.3% to 18.6%). In 2023, higher AU was associated with patient factors (medical devices, inpatient location, obesity, 4–17 day hospital stays, and suburban residence) and hospital factors (Northeast and South regions, AU audits). Conclusions One in two inpatients received an antimicrobial in 2023, similar to 2015. However, changes in AU by inpatient location and antimicrobial class suggest evolving prescribing practices and may inform targeted surveillance and stewardship efforts.