| Description: |
Background Clostridioides difficile infection (CDI) accounts for 450,000 cases and $6.3 billion in healthcare costs annually in the US. The June 2021 IDSA/SHEA guideline update recommended fidaxomicin over vancomycin for initial and recurrent CDI and adjuvant bezlotoxumab for high-risk patients. We evaluated the impact of this update on CDI management, outcomes, and healthcare utilization. Methods We conducted a retrospective study using Epic Cosmos (Epic EHR data, US only, 2018-2024), including all adult inpatient/outpatient encounters with a CDI diagnosis. An interrupted time series analysis evaluated trends in monthly utilization of enteral fidaxomicin, vancomycin, metronidazole, and IV bezlotoxumab; 30-day CDI recurrence (logistic regression); mean length of stay (LOS) (linear regression); and total monthly CDI-related costs (linear regression; including antibiotics, LOS, and recurrence-related readmissions) before (Jun 2018-May 2021) and after (July 2021-Dec 2024) the guideline update. Results We identified 1,204,726 CDI encounters. Following the guideline update, fidaxomicin, vancomycin, and bezlotoxumab use increased (3.1% to 9.6%; 26.4% to 30.1%, and 0.1% to 0.5%, respectively), while metronidazole use decreased (6.6% to 3.5%, Figures 1-2). The guideline update was associated with an immediate 4% reduction in the odds of 30-day recurrence (OR 0.96, 95% CI 0.94-0.97, p< 0.001) followed by a flattening in recurrence trend post-intervention (interaction OR 0.98, p< 0.001, Figures 3-4). Mean LOS increased immediately (β=0.12 log-days, 95% CI 0.07-0.16, p< 0.001), but declined significantly over time (interaction β=–0.10, p< 0.001). Total monthly cost increased sharply post-intervention (β=$19.5 million, 95% CI: $10.6M–28.4M, p< 0.001); but slopes changes were not significant (interaction β=$2.85M, p=0.2). Conclusion Adoption of the updated CDI guidelines was associated with reduced recurrence and declining LOS. Although monthly costs increased substantially ... |