title: Clostridium difficile-associated diarrhea: epidemiology, risk factors, and infection control.
abstract: OBJECTIVE
  To evaluate the effectiveness of specific infection control measures on the incidence of Clostridium difficile-associated diarrhea (CDAD) and to identify risk factors for its development.
  
  
  METHODS
  370-bed, tertiary-care teaching hospital with approximately 12,000 to 15,000 admissions per year.
  
  
  METHODS
  Several infection control measures were implemented in 1991 and 1992, and the attack rates of CDAD were calculated quarterly. Antibiotic use for 1988 through 1993 was analyzed. A case-control study was conducted from January 1992 to December 1992 to identify risk factors for acquisition of CDAD.
  
  
  RESULTS
  From 1989 to 1992, the attack rate of CDAD increased from 0.49% to 2.25%. An increase in antibiotic use preceded the rise in the incidence of CDAD in 1991. Despite implementation of various infection control measures, the attack rate decreased to 1.32% in 1993, but did not return to baseline. Ninety-two cases and 78 controls (patients with diarrhea but with negative toxin assay) were studied. By univariate analysis, history of prior respiratory tract infections (odds ratio [OR], 3.6; 95% confidence interval [CI95], 1.2-10.4), the number of antibiotics, and the duration of exposure to second-generation cephalosporins (OR, 3.55; CI95, 1.47-9.41) and to ciprofloxacin (OR, 7.27; CI95, 1.13-166.0) were related significantly to the development of CDAD. By stepwise logistic regression analysis, only exposure to antibiotics and prior respiratory tract infections (P = .0001 and .0203, respectively) were found to be significant.
  
  
  CONCLUSIONS
  Antibiotic pressure might have contributed to failure of infection control measures to reduce the incidence of CDAD to baseline.
authors.affiliation: Division of Infectious Disease and Immunology, University of Massachusetts Medical Center, Worcester 01655, USA.
authors.forename: K K
authors.initials: KK
authors.lastname: Lai
authors.forename: Z S
authors.initials: ZS
authors.lastname: Melvin
authors.forename: M J
authors.initials: MJ
authors.lastname: Menard
authors.forename: H R
authors.initials: HR
authors.lastname: Kotilainen
authors.forename: S
authors.initials: S
authors.lastname: Baker
mesh_terms: D000704:Analysis of Variance; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D016022:Case-Control Studies; D016360:Clostridioides difficile / Q000302:isolation & purification; D003015:Clostridium Infections / Q000453:epidemiology / Q000517:prevention & control*; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology* / Q000517:prevention & control; D003967:Diarrhea / Q000453:epidemiology / Q000382:microbiology* / Q000517:prevention & control; D005260:Female; D006235:Hand Disinfection; D006784:Hospitals, Teaching; D006801:Humans; D015994:Incidence; D017053:Infection Control / Q000379:methods*; D016015:Logistic Models; D008297:Male; D008404:Massachusetts / Q000453:epidemiology; D008875:Middle Aged; D016017:Odds Ratio; D012307:Risk Factors; D018709:Statistics, Nonparametric; D016635:Universal Precautions
chemical_list: D000900:Anti-Bacterial Agents