title: Effect of Clostridium difficile Prevalence in Hospitals and Nursing Homes on Risk of Infection.
abstract: OBJECTIVE
  To assess the effect of facility Clostridium difficile infection (CDI) prevalence on risk of healthcare facility (HFC) acquired CDI.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Medicare fee-for-service (FFS) claims and skilled nursing facility (SNF) Minimum Data Set 3.0 assessments.
  
  
  METHODS
  Medicare beneficiaries with 90 days or more of no contact with a HCF before a hospital admission without a CDI diagnosis. Participants were separated into two cohorts: discharged to the community and discharged to a SNF.
  
  
  METHODS
  Risk of HCF-acquired CDI associated with CDI prevalence at the index facility measured according to 30-day rehospitalization with a discharge diagnosis of CDI or diagnosis in the SNF after admission. Hospital and SNF CDI prevalence were categorized into three groups: 0% and above and below the median value for facilities with greater than 0% prevalence.
  
  
  RESULTS
  Of 817,900 eligible individuals, there were 553,423 admissions in the first cohort (discharged to the community) and 315,109 in the second (discharged to a SNF). In the first cohort, the risk of HCF-acquired CDI was higher for individuals admitted to hospitals with CDI prevalence less than the median (relative risk (RR) = 1.58, 95% confidence interval (CI) = 1.18-2.12) and greater than the median (RR = 2.56, 95% CI = 1.91-3.45) than for those with no CDI. In the second cohort, the risk of HCF-acquired CDI was greater for individuals admitted to a hospital (RR = 1.89, 95% CI = 1.49-2.39) and a SNF (RR = 1.48, 95% CI = 1.31-1.67) with CDI prevalence greater than the median.
  
  
  CONCLUSIONS
  The risk of HCF-acquired CDI is greater for noninfected individuals admitted to hospitals and SNFs with a high prevalence of CDI.
authors.affiliation: Department of Health Care Policy, School of Medicine, Harvard University, Boston, Massachusetts.
authors.forename: Nina R
authors.initials: NR
authors.lastname: Joyce
authors.affiliation: Division of Infectious Diseases, Rhode Island Hospital, Providence, Rhode Island.
authors.forename: Eleftherios
authors.initials: E
authors.lastname: Mylonakis
authors.affiliation: Department of Health Services, Policy and Practice, Brown University, Providence, Rhode Island.|Providence Veterans Administration Medical Center, Providence, Rhode Island.
authors.forename: Vincent
authors.initials: V
authors.lastname: Mor
mesh_terms: D016360:Clostridioides difficile / Q000302:isolation & purification*; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control; D006761:Hospitals / Q000706:statistics & numerical data*; D006801:Humans; D007345:Insurance Claim Review; D006278:Medicare; D009735:Nursing Homes / Q000706:statistics & numerical data*; D015995:Prevalence; D012189:Retrospective Studies; D018570:Risk Assessment; D014481:United States / Q000453:epidemiology
keywords: Clostridium Difficile; Infectious disease; hospital-acquired infection; nursing home