Current projects study veteran patients with chronic ulcers and MRSA colonization and
infection, patients with imipenem-resistant P. aeruginosa colonization and infection, the
relationships between staffing pattern, severity of illness and nosocomial infections in
intensive care units and infection control practices for veteran patients with suspected
Nosocomial infections are often caused by antimicrobial-resistant pathogens such as
vancomycin resistant enterococci (VRE) and are a major cause increased morbidity, mortality
and cost in hospitalized patients. Nosocomial bloodstream infections (BSI) add 7 to 21 days
to the length of stay and cost institutions $3,061 to $40,000. The average cost of treating
patients with VRE BSI has been estimated as 30% more than vancomycin sensitive enterococcal
BSI. In addition, the attributable mortality of VRE BSI has been estimated as 37%.
Preventing VRE infection and VRE transmission is clearly important and understanding the
risk factors for each is a necessary first step. The goal of this three year study is to
identify potentially effective interventions for the prevention of VRE infection and
colonization Before testing interventions, we need to identify risk factors for VRE
infection which will allow us to (1) identify potentially effective interventions and (2)
focus on patients at highest risk for VRE infection. We will study the effect of antibiotic
use, particularly vancomycin, and impaired host defenses on VRE infection in a large cohort
study of VRE colonized patients. The goal is to develop a statistical model, which will
allow us to identify alterable risk factors, which could reduce the risk of VRE infection.
Many case-control studies have been performed to study VRE colonization and infection;
however, most of these studies were small with insufficient sample sizes for multivariate
modeling. Vancomycin-resistant enterococci (VRE) can be transmitted from patient to patient.
We propose to model the ecological relationship between the rate of VRE transmission and the
pre-existing prevalence of VRE in an ICU to determine whether the relationship is linear or
exponential. The objective is to determine at what point the rate of transmission increases
significantly that specific interventions should occur (e.g. reverse isolation of all
patients, close unit to new admissions). Controlling health care costs is an important part
of health care today and is particularly important in the capitated reimbursement system
that VHA is adopting. Potential interventions to prevent VRE infections and VRE transmission
must be cost-effective to the healthcare system to justify their adoption. The current study
will quantify the operational costs associated with VRE colonization and infection in
hospitalized patients compared to their non-colonized counterparts. Patients from the
intensive care units with and without VRE colonization will be covaried for severity of
illness and stratified by Major Diagnostic Category (by primary ICD-9 code) and marginal
health care costs compared. This estimate can then be used to examine the potential
cost-effectiveness of identified interventions, and to justify the system-wide costs of
implementing these interventions.
Patients from the intensive care units with or without VRE colonization.