In a significant longitudinal study spanning 17 years in two hospitals in Québec, Canada, researchers delved into the intricate link between the use of antibiotics, particularly fluoroquinolones, and healthcare-associated Clostridioides difficile infections (HA-CDI). Emanating from a need to better understand the epidemiology of Clostridioides difficile infections in the wake of the 2003 pandemic, this study sought to evaluate how antibiotic stewardship could effectively help in mitigating the incidence of HA-CDI and the prevalence of the NAP1/027 strain.
This comprehensive study painted a clear picture of the trends in Clostridioides difficile infections and antibiotic usage, revealing a significant decline in HA-CDI cases from 26.5 per 10,000 patient days in 2003, to 4.9 in 2020. Notably, throughout this investigative period, there appeared to be a surge in the use of third-generation cephalosporins, coinciding with a marked decrease in the usage of fluoroquinolones and clindamycin. A correlational observation was drawn, where this reduction in fluoroquinolone use was definitively associated with a decrease in HA-CDI incidence and an approximately 80% decrease in the prevalence of the NAP1/027 strain in both hospitals.
Interestingly, while the consumption of antibiotics increased overall, the usage of high-risk antibiotics such as fluoroquinolones, second-generation cephalosporins, and clindamycin decreased, as narrated by the investigators. These declining trends had a significant impact, ultimately leading to a decrease over time in the Clostridioides difficile NAP1/027 strain, which is inherently resistant to fluoroquinolones.
To generate robust findings, the study used a dynamic regression time-series model to assess the impact of antibiotic usage on HA-CDI incidence. The study data was examined biannually from 2003 to 2020, conducting comparative analyses of antibiotic utilization and the percentage of NAP1/027 strains.
The outcome of this study, although limited in its geographical scope and potentially confounded by concurrent infection control interventions during the study period, reveals a compelling narrative. The decrease in HA-CDI incidence and the proportion of NAP1/027 C. difficile strains in one of the participating hospitals can be directly linked to the reduced use of high-risk antibiotics, notably fluoroquinolones. This underlines the importance of antibiotic stewardship as an effective hotspot control strategy against HA-CDI rates and hypervirulent strains within hospitals.