Major article
Exposure to hospital roommates as a risk factor for health care–associated infection

https://doi.org/10.1016/j.ajic.2009.08.016Get rights and content

Background

Numerous patient- and hospital-level characteristics have been established as risk factors for the transmission of health care–associated infections (HAIs). Few studies have quantitatively assessed the impact of exposure to hospital roommates on the acquisition of infections. This study evaluated the association between roommate exposures and the risk of HAIs.

Methods

A retrospective cohort of adult patients admitted to a Canadian teaching hospital between June 30, 2001, and December 31, 2005, was studied. Exposures were characterized as total daily roommate exposures and daily unique roommate exposures. Outcomes examined were methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), and Clostridium difficile.

Results

The number of roommate exposures per day was significantly associated with MRSA and VRE infection or colonization (MRSA: hazard ratio [HR] = 1.10, 95% confidence interval [CI] = 1.05 to 1.15; VRE: HR = 1.11, 95% CI = 1.02 to 1.21), and with C difficile infection (HR = 1.11, 95% CI = 1.03 to 1.19). A significant association also was found for number of unique roommate exposures per day and VRE (HR = 1.15, 95% CI = 1.02 to 1.28).

Conclusions

The significant associations found between daily roommate exposures and the infection outcomes suggest a possible role for limiting patient-to-patient contact in an infection prevention and control program in this facility. These findings have implications for the deployment and design of acute care hospitals.

Section snippets

Study population

A retrospective cohort was created from patients admitted to a Canadian tertiary care teaching hospital in southeastern Ontario between April 1, 2001, and March 31, 2006. During the study period, the hospital admitted approximately 17,200 patients per year into 451 in-patient beds. The bed distribution was 107 private beds each in its own room, 166 double-occupancy beds in 83 rooms, 18 triple-occupancy beds in 6 rooms, 76 quadruple- occupancy beds in 19 rooms, as well as 3 open-bay areas in the

Results

Initially, the study population consisted of 94,784 patients and 205,902 patient observations (one observation for every bed occupied by the patient). Ten patients (10 observations) were removed who were not actually admitted to the hospital, 16,865 patients (35,288 observations) were removed for being in one of the in-patient units excluded from the study, 101 patients (162 observations) were removed for being under age 16 years, 3923 patients (8445 observations) were removed because they were

Discussion

The literature on the topic of direct associations between exposure to or the number of hospital roommates and the incidence of HAIs is very limited. While there have been numerous studies on single-occupancy versus multiple-occupancy rooms,10, 11, 14, 32, 33, 34 very few epidemiologic studies investigating the role of hospital roommates in infection/colonization acquisition have been published. The current study supports the hypothesis that for MRSA, VRE, and C difficile, exposure to hospital

References (44)

  • Centers for Disease Control and Prevention. Campaign to Prevent Antimicrobial Resistance in Healthcare Settings....
  • M. Bowbrow et al.

    Inpatient care facilities

  • E. Girou et al.

    Risk factors and outcome of nosocomial infections: results of a matched case-control study of ICU patients

    Am J Respir Crit Care Med

    (1998)
  • A.E. Simor et al.

    the Canadian Nosocomial Infection Surveillance Program (Health Canada). The evolution of methicillin-resistant Staphylococcus aureus in Canadian hospitals: 5 years of national surveillance

    CMAJ

    (2001)
  • K.Z. Shirani et al.

    Effects of environment of infection in burn patients

    Arch Surg

    (1986)
  • Coalition for Health Environments Research. The use of single patient rooms versus multiple occupancy rooms in acute...
  • C.C. Kibbler et al.

    The effect of increased bed numbers on MRSA transmission in acute medical wards

    J Hosp Infect

    (1997)
  • R. Ulrich et al.

    The role of the physical environment in the hospital of the 21st century: a once-in-a-lifetime opportunity

    Report to The Center for Health Design for the Designing the 21st Century Hospital Project

    (September 2004)
  • L.K. Archibald et al.

    Patient density, nurse-to-patient ratio and nosocomial infection risk in a pediatric cardiac intensive care unit

    Pediatr Infect Dis J

    (1997)
  • V.T. Chang et al.

    The role of physical proximity in nosocomial diarrhea

    Clin Infect Dis

    (2000)
  • S. Harbarth et al.

    Outbreak of Enterobacter cloacae related to understaffing, overcorowding, and poor hygiene practices

    Infect Control Hosp Epidemiol

    (1999)
  • D.J. Austin et al.

    Vancomycin-resistant enterococci in intensive-care hospital settings: transmission dynamics, persistance, and the impact of infection control programs

    Proc Natl Acad Sci USA

    (1999)
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