Clostridioides difficile infection (CDI) in a previous room occupant predicts CDI in subsequent room occupants across different hospital settings

Background: Previous single-center studies suggest that exposure to a room previously occupied by a patient with CDI may increase the risk of CDI in subsequent patients. We evaluated the risk of previous room occupant on CDI risk across 5 adult hospitals. Methods: This is a non-concurrent cohort study of adult inpatients admitted to 5 hospitals. Exposed rooms were identified as being occupied by a patient diagnosed with CDI and a logistic regression was performed to assess if staying in an exposed room increases the risk of CDI in subsequent patients. Results: Patients admitted to a room that was previously occupied by a patient with CDI had a 27% increased odds of subsequently being diagnosed with CDI (odds ratio (OR)=1.269; 95% confidence interval (CI)= 1.12-1.44) if exposed within the last 90 days and 40% increased odds (OR=1.401; 95% CI= 1.25-1.57) if exposed in the last 365 days after controlling for previous admissions and length of stay. Cumulative patient-day exposure to previously CDI-positive occupied rooms within both 90 and 365 days were also found to be independently significant, with a 4.5% (OR 1.045; 95% CI = 1.03-1.06) and 4.2% (OR 1.042; 95% CI = 1.03-1.06) increase in odds of CDI with each day of exposure respectively.