title: Identification of population at risk for future Clostridium difficile infection following hospital discharge to be targeted for vaccine trials.
abstract: BACKGROUND
  Efforts to develop a Clostridium difficile vaccine are underway; identification of patients at risk for C. difficile infection (CDI) is critical to inform vaccine trials. We identified groups at high risk of CDI ≥ 2 8 days after hospital discharge.
  
  
  METHODS
  Hospital discharge data and pharmacy data from two large academic centers, in New York and Connecticut, were linked to active population-based CDI surveillance data from the Emerging Infections Program (EIP). Adult residents of the EIP surveillance area were included if they had an inpatient stay at a study hospital without prior history of CDI. The primary outcome was CDI by either toxin or molecular assay ≥ 28 days after an index hospitalization. Important predictors of CDI ≥ 28 days post discharge were initially identified through a Cox proportional hazards model (stepwise backward selection) using a derivation cohort; final model parameters were used to develop a risk score evaluated in the validation cohort.
  
  
  RESULTS
  Of the 35,186 index hospitalizations, 288 (0.82%) had CDI ≥ 28 days post discharge. After parameter selection, age, number of hospitalizations in the prior 90 days, admission diagnosis, and the use of 3rd/4th generation cephalosporin, clindamycin or fluoroquinolone antibiotic classes remained in the model. Using the validation cohort, the risk score was predictive (p<0.001) with a c-score of 0.75. Based on the distribution of scores in the derivation cohort, we divided the patients into low and high risk groups. In the high risk group, 1.6% experienced CDI ≥ 28 days post discharge compared to 0.3% among our low risk group.
  
  
  CONCLUSIONS
  Our study identified specific parameters for a risk score that can be applied at discharge to identify a patient population whose risk of CDI ≥ 28 days following an acute care hospitalization was 5 times greater than other patients.
authors.affiliation: Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, GA, United States. Electronic address: jbaggs@cdc.gov.
authors.forename: James
authors.initials: J
authors.lastname: Baggs
authors.affiliation: Connecticut Emerging Infections Program, Yale School of Public Health, New Haven, CT, United States.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Yousey-Hindes
authors.affiliation: University of Rochester Medical Center, Rochester, NY, United States.
authors.forename: Elizabeth Dodds
authors.initials: ED
authors.lastname: Ashley
authors.affiliation: Connecticut Emerging Infections Program, Yale School of Public Health, New Haven, CT, United States.
authors.forename: James
authors.initials: J
authors.lastname: Meek
authors.affiliation: University of Rochester Medical Center, Rochester, NY, United States.
authors.forename: Ghinwa
authors.initials: G
authors.lastname: Dumyati
authors.affiliation: Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, GA, United States; Atlanta Research and Education Foundation, Atlanta, GA, United States.
authors.forename: Jessica
authors.initials: J
authors.lastname: Cohen
authors.affiliation: Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, GA, United States.
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Wise
authors.affiliation: Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, GA, United States.
authors.forename: L Clifford
authors.initials: LC
authors.lastname: McDonald
authors.affiliation: Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, GA, United States.
authors.forename: Fernanda C
authors.initials: FC
authors.lastname: Lessa
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000276:immunology*; D002986:Clinical Trials as Topic; D016360:Clostridioides difficile / Q000302:isolation & purification*; D003015:Clostridium Infections / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control*; D003237:Connecticut / Q000453:epidemiology; D003661:Decision Support Techniques; D005260:Female; D006761:Hospitals; D006801:Humans; D008297:Male; D008875:Middle Aged; D009518:New York / Q000453:epidemiology; D010351:Patient Discharge; D012189:Retrospective Studies; D018570:Risk Assessment; D055815:Young Adult
chemical_list: D001428:Bacterial Vaccines
keywords: Administrative data; Anti-bacterial agents; Clostridium difficile infection; Health care-associated infections; Vaccines