The Association Between the Frequency of Interruptions in Antibiotic Exposure and the Risk of Health Care-Associated Clostridiodes difficile Infection

BACKGROUND: Although antibiotic use is an established risk factor for health care-associated Clostridiodes difficile infection, estimates of the association between infection and antibiotic use vary, depending upon how antibiotic exposure is measured. OBJECTIVES: The purpose of this study was to explore the association between the frequency of interruptions in antibiotic exposure and the risk of health care-associated C difficile infection. METHODS: A retrospective chart review cohort study was conducted of all inpatients between 2011and 2016 from a single academic health center who received at least 1 dose of a systemic antibacterial for a cumulative duration of >3 days and ≤30 days. The measures of antibiotic exposure examined were duration—cumulative total calendar days of antibiotics therapy—and continuity—the frequency of interruptions in antibiotic exposure that was defined as the number of antibiotic treatment courses. RESULTS: A total of 52,445/227,967 (23%) patients received antibacterial therapy for >3 days and ≤30 days during their hospitalization. Of these, 1161 out of 52,445 (2.21%) were patients with health care-associated C difficile infection. An adjusted multivariable logistic regression analysis revealed that the risk of C difficile increased with longer cumulative days (odds ratio = 2.7; comparison of >12 days to ≤5 days) and fewer interruptions of antibiotic treatment (odds ratio = 0.78; comparison of >3 discrete antibiotic treatment courses to 1 course or continuous antibiotic treatment course; all P values < 0.05). CONCLUSIONS: For patients who received the same number of cumulative days of therapy, the patients who had more frequently interrupted courses of antibiotic therapy were less likely to experience health care-associated C difficile infection. (Curr Ther Res Clin Exp. 2020; 81:XXX–XXX)