title: Receipt of Antibiotics in Hospitalized Patients and Risk for Clostridium difficile Infection in Subsequent Patients Who Occupy the Same Bed.
abstract: OBJECTIVE
  To assess whether receipt of antibiotics by prior hospital bed occupants is associated with increased risk for CDI in subsequent patients who occupy the same bed.
  
  
  METHODS
  This is a retrospective cohort study of adult patients hospitalized in any 1 of 4 facilities between 2010 and 2015. Patients were excluded if they had recent CDI, developed CDI within 48 hours of admission, had inadequate follow-up time, or if their prior bed occupant was in the bed for less than 24 hours.
  
  
  METHODS
  The primary exposure was receipt of non-CDI antibiotics by the prior bed occupant and the primary outcome was incident CDI in the subsequent patient to occupy the same bed. Incident CDI was defined as a positive result from a stool polymerase chain reaction for the C difficile toxin B gene followed by treatment for CDI. Demographics, comorbidities, laboratory data, and medication exposures are reported.
  
  
  RESULTS
  Among 100 615 pairs of patients who sequentially occupied a given hospital bed, there were 576 pairs (0.57%) in which subsequent patients developed CDI. Receipt of antibiotics in prior patients was significantly associated with incident CDI in subsequent patients (log-rank P < .01). This relationship remained unchanged after adjusting for factors known to influence risk for CDI including receipt of antibiotics by the subsequent patient (adjusted hazard ratio [aHR], 1.22; 95% CI, 1.02-1.45) and also after excluding 1497 patient pairs among whom the prior patients developed CDI (aHR, 1.20; 95% CI, 1.01-1.43). Aside from antibiotics, no other factors related to the prior bed occupants were associated with increased risk for CDI in subsequent patients.
  
  
  CONCLUSIONS
  Receipt of antibiotics by prior bed occupants was associated with increased risk for CDI in subsequent patients. Antibiotics can directly affect risk for CDI in patients who do not themselves receive antibiotics.
authors.affiliation: Division of Digestive and Liver Diseases, Columbia University Medical Center, New York, New York.
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Freedberg
authors.affiliation: Department of Biomedical Informatics, New York-Presbyterian Hospital, New York, New York.
authors.forename: Hojjat
authors.initials: H
authors.lastname: Salmasian
authors.affiliation: Department of Epidemiology, Mailman School of Public Health, School of Nursing, Columbia University, New York, New York.
authors.forename: Bevin
authors.initials: B
authors.lastname: Cohen
authors.affiliation: Division of Digestive and Liver Diseases, Columbia University Medical Center, New York, New York.
authors.forename: Julian A
authors.initials: JA
authors.lastname: Abrams
authors.affiliation: Department of Epidemiology, Mailman School of Public Health, School of Nursing, Columbia University, New York, New York.
authors.forename: Elaine L
authors.initials: EL
authors.lastname: Larson
mesh_terms: D000368:Aged; D000863:Antacids / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001513:Beds; D016360:Clostridioides difficile; D003015:Clostridium Infections / Q000188:drug therapy* / Q000635:transmission*; D015331:Cohort Studies; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D005260:Female; D006760:Hospitalization; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D009519:New York City / Q000453:epidemiology; D012189:Retrospective Studies; D012306:Risk; D012307:Risk Factors
chemical_list: D000863:Antacids; D000900:Anti-Bacterial Agents