title: A Comprehensive Assessment Across the Healthcare Continuum: Risk of Hospital-Associated Clostridium difficile Infection Due to Outpatient and Inpatient Antibiotic Exposure.
abstract: BACKGROUND
  Limitations in sample size, overly inclusive antibiotic classes, lack of adjustment of key risk variables, and inadequate assessment of cases contribute to widely ranging estimates of risk factors for Clostridium difficile infection (CDI).
  
  
  OBJECTIVE
  To incorporate all key CDI risk factors in addition to 27 antibiotic classes into a single comprehensive model.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Kaiser Permanente Southern California.
  
  
  METHODS
  Members of Kaiser Permanente Southern California at least 18 years old admitted to any of its 14 hospitals from January 1, 2011, through December 31, 2012.
  
  
  METHODS
  Hospital-acquired CDI cases were identified by polymerase chain reaction assay. Exposure to major outpatient antibiotics (10 classes) and those administered during inpatient stays (27 classes) was assessed. Age, sex, self-identified race/ethnicity, Charlson Comorbidity Score, previous hospitalization, transfer from a skilled nursing facility, number of different antibiotic classes, statin use, and proton pump inhibitor use were also assessed. Poisson regression estimated adjusted risk of CDI.
  
  
  RESULTS
  A total of 401,234 patients with 2,638 cases of incident CDI (0.7%) were detected. The final model demonstrated highest CDI risk associated with increasing age, exposure to multiple antibiotic classes, and skilled nursing facility transfer. Factors conferring the most reduced CDI risk were inpatient exposure to tetracyclines and first-generation cephalosporins, and outpatient macrolides. CONCLUSIONS Although type and aggregate antibiotic exposure are important, the factors that increase the likelihood of environmental spore acquisition should not be underestimated. Operationally, our findings have implications for antibiotic stewardship efforts and can inform empirical and culture-driven treatment approaches.
authors.affiliation: 1Department of Research and Evaluation,Kaiser Permanente Southern California,Pasadena,California.
authors.forename: Sara Y
authors.initials: SY
authors.lastname: Tartof
authors.affiliation: 2Department of Infectious Diseases,Southern California Permanente Medical Group,Harbor City,California.
authors.forename: Gunter K
authors.initials: GK
authors.lastname: Rieg
authors.affiliation: 1Department of Research and Evaluation,Kaiser Permanente Southern California,Pasadena,California.
authors.forename: Rong
authors.initials: R
authors.lastname: Wei
authors.affiliation: 1Department of Research and Evaluation,Kaiser Permanente Southern California,Pasadena,California.
authors.forename: Hung Fu
authors.initials: HF
authors.lastname: Tseng
authors.affiliation: 1Department of Research and Evaluation,Kaiser Permanente Southern California,Pasadena,California.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Jacobsen
authors.affiliation: 1Department of Research and Evaluation,Kaiser Permanente Southern California,Pasadena,California.
authors.forename: Kalvin C
authors.initials: KC
authors.lastname: Yu
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D002140:California / Q000453:epidemiology; D016360:Clostridioides difficile / Q000302:isolation & purification; D015897:Comorbidity; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology*; D004761:Enterocolitis, Pseudomembranous / Q000453:epidemiology* / Q000209:etiology*; D005006:Ethnicity / Q000706:statistics & numerical data; D005260:Female; D006761:Hospitals; D006801:Humans; D007297:Inpatients; D008297:Male; D008875:Middle Aged; D010045:Outpatients; D016012:Poisson Distribution; D016133:Polymerase Chain Reaction; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents