Change in Antimicrobial Use during COVID-19 Pandemic in South Carolina Hospitals: A Multicenter Observational Cohort Study

Winders, Hana R.; Bailey, Pamela; Kohn, Joseph; Faulkner-Fennell, Carmen M.; Utley, Sara; Lantz, Evan; Sarbacker, Lloyd; Justo, Julie Ann; Bookstaver, P. Brandon; Weissman, Sharon; Ruegner, Hannah; Al-Hasan, Majdi N.

This retrospective cohort study examined the impact of the pandemic on antimicrobial use (AU) in South Carolina hospitals. AU in days of therapy (DOT) per 1000 days-present was evaluated in 17 hospitals in South Carolina. Matched-pairs mean difference was used to compare AU during the pandemic (March-June 2020) to that during the same months in 2019 in hospitals that did and did not admit patients with COVID-19. There was a 6.6% increase in overall AU in the 7 hospitals admitting patients with COVID-19 (from 530.9 to 565.8; mean difference: 34.9 DOT/1000 days-present, 95% CI: 4.3, 65.6; p=0.03). There was no significant change in overall AU in the remaining 10 hospitals that did not admit patients with COVID-19 (mean difference 6.0 DOT/1000 days-present, 95% CI: -55.5, 67.6; p=0.83). Most of the increase in AU in the 7 hospitals that admitted patients with COVID-19 was observed in broad-spectrum antimicrobial agents. A 16.4% increase was observed in agents predominantly used for hospital-onset infections (from 122.3 to 142.5; mean difference: 20.1 DOT/1000 days-present, 95% CI: 11.1, 29.1, p=0.002). There was also a 9.9% increase in the use of anti-MRSA agents (from 66.7 to 73.3; mean difference: 6.6 DOT/1000 days-present, 95% CI: 2.3, 10.8; p=0.01). COVID-19 pandemic appears to drive overall and broad-spectrum antimicrobial use in South Carolina hospitals admitting patients with COVID-19. Additional antimicrobial stewardship resources are needed to curtail excessive antimicrobial use in hospitals to prevent subsequent increases in antimicrobial resistance and Clostridioides difficile infection rates given the continuing nature of the pandemic.