Examining the association between hospital-onset Clostridium difficile infection and multiple-bed room exposure: a case-control study

Abstract

Objective: To determine whether assignment to a multiple-bed room increased the risk of hospital-onset C. difficile diarrhea (HO-CDI).

Design: Case-control study.

Setting: San Francisco General Hospital and Trauma Center.PopulationAdult general medical and surgical inpatients.

Methods: Consecutive cases of HO-CDI were identified between January 1, 2010, and December 31, 2015. To investigate the effect of multiple-bed room exposure both at admission and at the time of symptom onset, 2 sets of controls were selected from the general medical/surgical inpatient population using incidence density sampling. Conditional logistic regression was used to estimate the relationship between room assignment (single bed vs multiple beds) and the development of HO-CDI.

Results: In total, 187 cases were identified and matched with 512 and 515 controls for the admission and at-diagnosis analyses, respectively. The adjusted rate ratio (RR) associated with the development HO-CDI associated with multiple-bed room exposure during the 7 and 14 days immediately prior to HO-CDI diagnosis were 1.08 (95% confidence interval [CI], 0.93-1.25; P=.31) and 0.96 (95% CI, 0.93-1.18; P=.12), respectively. Furthermore, no significant association was detected in the analysis of the first 7 and 14 days after case admission or among patients with Charlson comorbidity scores ≥4 in either period.

Conclusion: Assignment of patients to multiple-bed rooms on general medical and surgical wards was not associated with an increased risk in the development of HO-CDI. Future investigation should be performed with larger cohorts in multiple sites to more definitively address the question because this issue could have implications for patient room assignment and hospital design.