title: Two time-series analyses of the impact of antibiotic consumption and alcohol-based hand disinfection on the incidences of nosocomial methicillin-resistant Staphylococcus aureus infection and Clostridium difficile infection.
abstract: OBJECTIVE
  To determine the impact of antibiotic consumption and alcohol-based hand disinfection on the incidences of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) infection and Clostridium difficile infection (CDI).
  
  
  METHODS
  Two multivariate time-series analyses were performed that used as dependent variables the monthly incidences of nosocomial MRSA infection and CDI at the Freiburg University Medical Center during the period January 2003 through October 2007. The volume of alcohol-based hand rub solution used per month was quantified in liters per 1,000 patient-days. Antibiotic consumption was calculated in terms of the number of defined daily doses per 1,000 patient-days per month.
  
  
  RESULTS
  The use of alcohol-based hand rub was found to have a significant impact on the incidence of nosocomial MRSA infection (P< .001). The multivariate analysis (R2=0.66) showed that a higher volume of use of alcohol-based hand rub was associated with a lower incidence of nosocomial MRSA infection. Conversely, a higher level of consumption of selected antimicrobial agents was associated with a higher incidence of nosocomial MRSA infection. This analysis showed this relationship was the same for the use of second-generation cephalosporins (P= .023), third-generation cephalosporins (P= .05), fluoroquinolones (P= .01), and lincosamides (P= .05). The multivariate analysis (R2=0.55) showed that a higher level of consumption of third-generation cephalosporins (P= .008), fluoroquinolones (P= .084), and/or macrolides (P= .007) was associated with a higher incidence of CDI. A correlation with use of alcohol-based hand rub was not detected.
  
  
  CONCLUSIONS
  In 2 multivariate time-series analyses, we were able to show the impact of hand hygiene and antibiotic use on the incidence of nosocomial MRSA infection, but we found no association between hand hygiene and incidence of CDI.
authors.affiliation: Department of Environmental Health Sciences, University Medical Center Freiburg, Freiburg, Germany. klaus.kaier@uniklinik-freiburg.de
authors.forename: Klaus
authors.initials: K
authors.lastname: Kaier
authors.forename: Christian
authors.initials: C
authors.lastname: Hagist
authors.forename: Uwe
authors.initials: U
authors.lastname: Frank
authors.forename: Andreas
authors.initials: A
authors.lastname: Conrad
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Meyer
mesh_terms: D000046:Academic Medical Centers; D000438:Alcohols / Q000008:administration & dosage*; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016360:Clostridioides difficile / Q000187:drug effects; D003428:Cross Infection / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D004202:Disinfectants / Q000008:administration & dosage; D004761:Enterocolitis, Pseudomembranous / Q000453:epidemiology* / Q000382:microbiology; D005858:Germany; D006235:Hand Disinfection / Q000379:methods*; D006801:Humans; D015994:Incidence; D007902:Length of Stay; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D015999:Multivariate Analysis; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D013997:Time Factors
chemical_list: D000438:Alcohols; D000900:Anti-Bacterial Agents; D004202:Disinfectants