Interhospital patient transfers between Ontario's academic and large community hospitals increase the risk of Clostridium difficile infection

Abstract

Background: The objective of this study is to determine the impact of interhospital patient transfers on the risk of Clostridium difficile infection (CDI).

Methods: The number of interhospital patient transfers and CDI cases for 11 academic and 40 large community hospitals (LCHs) were available from 2010-2015. These data were used to compute a CDI score for each sending facility as a measure of CDI pressure on the receiving facility. This CDI score was included as a variable in a multilevel mixed-effect Poisson regression model of CDI cases. Other covariates included year, CDI testing strategy, antimicrobial stewardship program (ASP), and criteria used for patient isolation. Hospital-specific random effects were estimated for the baseline rate of CDI (intercept) and ASP effect (slope).

Results: The CDI score ranged from 0-103, with a mean score ± SD of 20.4 ± 21.8. Every 10-point increase in the CDI score was associated with a 4.5% increase in the incidence of CDI in the receiving academic hospital (95% confidence interval [CI], 0.9-8.5) and 3.6% increase in the receiving LCHs (95% CI, 0.3-7). The random components of the model varied significantly, with a strong negative correlation of -0.85 (95% CI, -0.94 to -0.65).

Conclusions: Our results suggest interhospital patient transfers increase the risk of CDI. ASPs appear to reduce this risk; however, these ASP effects demonstrate significant heterogeneity across hospitals.

Keywords: Antimicrobial stewardship; CDI score; Clostridium difficile infection; Interhospital patient transfers; Network analysis.