Assessing the impact of the early COVID-19 era on antibiotic-resistant threats in inpatient settings: A mixed Poisson regression approach

Background: During the COVID-19 pandemic, increased antibiotic prescribing and infection prevention challenges coincided with antibiotic-resistant (AR) infection increases. Clostridioides difficile (C difficile) and methicillin-resistant Staphylococcus aureus (MRSA) are serious, costly AR threats. Health inequities in pan-demicera AR infections are not well-characterized.Methods: North Carolina statewide inpatient admissions were used to determine monthly admission rates and admission rate ratios (RRs) for C difficile and MRSA infections comparing 2017-2019 (prepandemic) to 2020 (pandemic exposure) using mixed-model Poisson regression adjusted for age, sex, comorbidities, and COVID-19. We assessed effect measure modification by admissions' community-level income, county rurality, and race and ethnicity. Mean total costs by infection type were compared.Results: With pandemic exposure, C difficile (adjusted RR = 0.90 [95% confidence interval [CI] 0.86, 0.94]) and MRSA pneumonia (adjusted RR = 0.97 [95% CI 0.91, 1.05]) decreased, while MRSA septicemia (adjusted RR = 1.13 [95% CI 1.07, 1.19]) increased. Effect measure modification was not detected. C difficile or MRSA coinfection nearly doubled mean costs among COVID-19 admissions.Conclusions: Despite decreases in C difficile and most MRSA infections, the early COVID-19 pandemic period saw continued increases in MRSA septicemia admissions in North Carolina. Equitable interventions to curb increases and reduce health care costs should be developed.(c) 2023 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.