Impact of Revised Infectious Diseases Society of America and Society for Healthcare Epidemiology of America Clinical Practice Guidelines on the Treatment of Clostridium difficile Infections in the United States.

Background: Our objective was to determine if oral vancomycin, fidaxomicin, and oral metronidazole use in the United States changed after publication of revised clinical practice guidelines for Clostridium difficile infection (CDI) in February 2018.

Methods: We obtained US antibiotic prescription data (IQVIA) from 2006-August 2019 and used guideline-recommended dosing regimens to estimate monthly numbers of 10-day treatment courses of vancomycin, fidaxomicin and metronidazole. Interrupted time-series analyses were performed, adjusted by month. We compared linear trends for monthly numbers of treatment courses in different time periods.

Results: Cumulative treatment courses of oral vancomycin and fidaxomicin increased by 54% (n = 226 166) and 48% (n = 18 518), respectively, in 18 months following guidelines compared with 18 months before; those of oral metronidazole decreased by 3% (n = 238 372). Monthly vancomycin and fidaxomicin use significantly increased throughout the period following revised guidelines (P < .0001 and P = .0002, respectively), whereas that of metronidazole decreased significantly (P < .0001). Monthly vancomycin use increased and metronidazole use decreased to a significantly greater extent after publication of revised guidelines than after publication of clinical trials establishing superiority of vancomycin over metronidazole (P < .0001).

Conclusions: Revised practice guidelines have had a significant impact on CDI treatment in the US. Clinical trial data used for the revised guidelines were available since 2007-2014 and 2011-2012 for oral vancomycin and fidaxomicin, respectively. Guidelines or guidance documents for treating CDI and other infections should be updated in more timely fashion.