Correlation between hospital-level antibiotic consumption and incident health care facility-onset Clostridium difficile infection

Background: The purpose of this single-center, ecologic study is to characterize the relationship between facility-wide (FacWide) antibiotic consumption and incident health care facility-onset Clostridium difficile infection (HO-CDI). Methods: FacWide antibiotic consumption and incident HO-CDI were tallied on a monthly basis and standardized, from January 2013 through April 2015. Spearman rank-order correlation coefficients were calculated using matched-months analysis and a 1-month delay. Regression analyses were performed, with P <.05 considered statistically significant. Results: FacWide analysis identified a matched-months correlation between ceftriaxone and HO-CDI (ρ = 0.44, P =.018). A unit of stem cell transplant recipients did not have significant correlation between carbapenems and HO-CDI in matched months (ρ = 0.37, P =.098), but a significant correlation was observed when a 1-month lag was applied (ρ = 0.54, P =.014). Discussion: Three statistically significant lag associations were observed between FacWide/unit-level antibiotic consumption and HO-CDI, and 1 statistically significant nonlagged association was observed FacWide. Antibiotic consumption may convey extended ward-level risk for incident CDI. Conclusions: Consumption of antibiotic agents may have immediate and prolonged influence on incident CDI. Additional studies are needed to investigate the immediate and delayed associations between antibiotic consumption and C difficile colonization, infection, and transmission at the hospital level.