Each week the monthly spotlight features a topic-related HSR&D study.
Spotlight on Healthcare Associated Infection Research: Costs and Benefits of Infection Prevention
Infections acquired within a healthcare setting are known as healthcare-associated infections (HAI), and according to the Centers for Disease Control & Prevention (CDC), on any given day, about one in 25[i] hospital patients has at least one HAI, and approximately 99,000 deaths[ii] each year are attributable to HAIs.
For healthcare organizations, preventive measures designed to reduce and eliminate HAIs are crucial for patient safety. As VA is one of the largest healthcare systems in the country—providing care to over 8.7 million Veterans in 300 VA hospitals and 827[iii] community-based outpatient clinics—preventing HAIs is a priority. Infection control and prevention is a VA-wide effort that includes VA's Office of Public Health in collaboration with other VA program offices, who work together to preventing and responding to HAIs. Investigators within VA's Health Services Research & Development Service (HSR&D) support those efforts through research studies that contribute to the evidence-base for effective HAI prevention practices and policy.
While a number of prevention strategies for healthcare-associated infections (HAIs) are available to providers and healthcare policy makers, the scope, cost, and effectiveness of these strategies is still not well-understood.
In this recently concluded HS&RD Career Development Program award study, investigators sought to apply cutting-edge empirical methods of estimating the costs and benefits of prevention efforts to reduce HAIs due to methicillin-resistant Staphylococcus aureus (MRSA) within the VA.
This project sought to understand any additional, outside benefits associated with decolonization of MRSA-positive Veterans; estimate the cost and healthcare use associated with hospital-acquired MRSA infections in the VA; and perform economic evaluations of infection control strategies.
Investigators used a nationwide microbiology database from VA patient encounters to construct measures of HAIs. This microbiology data was then integrated with other VA clinical, administrative, and economic data sets in order to estimate the consequences of HAIs including mortality, and pre- and post-discharge costs. Investigators also created a model that estimated the cost-effectiveness and budget impact of the VA’s MRSA Prevention Initiative. Investigators then estimated the increased risk of infection due to acquired MRSA colonization separate from imported MRSA colonization, and measured the proportion of MRSA infections that occurred during the post-discharge period.
Results indicated that excess cost and mortality of HAIs can be substantial both in the pre- and post-discharge period. However, these estimates are biased when the time-dependent nature of HAIs is not taken into account. Data analysis also showed that VA HAI interventions are cost-effective at a standard “willingness-to-pay” threshold. Finally, MRSA colonization is strongly associated with subsequent infection, and a large proportion of infections occurred in the post-discharge period.
Implications. Investigators expect that health economic evaluation, informed by VA-specific estimates of the cost and mortality consequences of HAIs, can be useful to policy makers considering different strategies to prevent the spread of infectious pathogens in the hospital. The results from these studies may help in the efficient allocation of limited resources within a fixed budget. Investigators recommend that any future work extend include infection control strategies designed to reduce HAIs associated with other organisms, such as Clostridium difficile and Gram-negative bacteria.
Principal Investigator. Richard E. Nelson, PhD, is a Core Investigator with the HSR&D
Center for Informatics, Decision-Enhancement and Analytic Sciences Center at the VA Salt Lake City Healthcare System.
- Nelson RE, Evans ME, Simbartl L, et al. Methicillin-resistant Staphylococcus aureus Colonization and Pre- and Post-hospital Discharge Infection Risk. Clinical Infectious Diseases. 2018 Aug 11. doi: 10.1093/cid/ciy507. [Epub ahead of print]
- Nelson RE, Jones M, Liu CF, et al. The impact of healthcare-associated methicillin-resistant Staphylococcus aureus infections on post-discharge healthcare costs and utilization. Infection Control Hospital Epidemiology. 2015 May;36(5):534-42. doi: 10.1017/ice.2015.22. Epub 2015 Feb 26.
- Nelson RE, Samore MH, Jones M, et al. Reducing Time-dependent Bias in Estimates of the Attributable Cost of Health Care-associated Methicillin-resistant Staphylococcus aureus Infections: A Comparison of Three Estimation Strategies. Medical Care. 2015 Sep;53(9):827-34.
- Nelson RE, Stevens VW, Khader K, et al. Economic Analysis of Veterans Affairs Initiative to Prevent Methicillin-Resistant Staphylococcus aureus Infections. American Journal of Preventive Medicine. 2016 May;50(5 Suppl 1):S58-S65.
(The HSR&D Gown and Glove Research Team)
Methicillin-resistant Staphylococcus aureus (MRSA) is an antibiotic-resistant bacteria that is a common cause of healthcare-associated infections (HAI). It is transmitted through direct or indirect contact with either individuals who are infected with MRSA or individuals who may be carrying the bacteria but are not infected. Often, healthcare workers (HCW) serve as a primary vector for transmission. In acute care settings, VA HCWs are required to use Contact Precautions (single room, gown and gloves for all patient-HCW contact, patient room restriction) for patients colonized with MRSA to prevent transmission to other patients. In long-term care settings, current CDC Multidrug Resistant Organisms Guidelines (MDROG) suggest modifying Contact Precautions, but there is little evidence to guide how to modify them. The use of gowns, gloves, and hand washing prevent MRSA transmission; however, their use detracts from a patient-centered, home-like environment—an important priority for nursing homes.
In this study, investigators sought to estimate the frequency of and risk factors for MRSA transmission to gowns and gloves when worn by healthcare workers providing care to VA Community Living Center (CLC) residents in seven states. MRSA surveillance results and clinical cultures were used to identify residents with a history of MRSA the year prior to enrollment. Two hundred residents were enrolled; 94 were MRSA colonized at enrollment.
Results showed that glove contamination was higher than gown contamination (20% vs. 11% of 1544 interactions). Transmission varied greatly by type of care from 0% to 19% for gowns and 7% to 37% for gloves. Identified high-risk activities included: changing dressings (e.g., wound, j-tube), dressing the resident, providing hygiene (e.g., brushing teeth, combing hair), and bathing the resident. Low-risk activities included giving medications, testing blood glucose, and feeding.
Additional findings from further analyses of the data and specimens collected for this study focused on the presence and transmission of other bacteria. Fifty-seven participants were colonized with an antibiotic-resistant Gram-negative bacteria (R-GNB). The high-risk and low-risk activities identified for transmission of R-GNB were similar to the activities identified for transmission of MRSA. Forty randomly selected participants were tested for toxigenic C. difficile at enrollment. None of them were positive, indicating a low prevalence of toxigenic C. difficile during endemic periods.
Implications. The VA Gown and Glove study goal was to identify the types of care provided in VA CLCs that are most likely to allow MRSA and other bacteria to spread to other residents. With this information, providers can be more specific in when HCWs need to wear gowns and gloves and wash their hands when caring for MRSA colonized residents, creating a more resident-centered, home-like environment in the Community Living Centers.
Results of this study been shared with study sites and the VA Multidrug Resistant Organism (MDRO) Prevention Program. The results also were incorporated into the VHA Guideline for Implementation of the VHA MRSA Prevention Initiative in CLCs, improving care for Veterans in the CLCs.
Principal Investigator. Mary-Claire Roghmann, MD, MS, is a Research Health Scientist and Staff Physician for the VA Maryland Health Care System.
Publications. This study resulted in the following publications:
- Pineles L, Morgan DJ, Lydecker A, et al. Transmission of methicillin-resistant Staphylococcus aureus to health care worker gowns and gloves during care of residents in Veterans Affairs nursing homes. American Journal of Infection Control. September 1, 2017;45(9):947-953.
- Blanco N, Pineles L, Lydecker AD, et al. Transmission of Resistant Gram-Negative Bacteria to Health Care Worker Gowns and Gloves during Care of Nursing Home Residents in Veterans Affairs Community Living Centers. Antimicrobial Agents and Chemotherapy. September 22, 2017;61(10).
- Roghmann MC, Andronescu L, Stucke E, et al. Clostridium difficile Colonization of Nursing Home Residents. Infection Control & Hospital Epidemiology. October 2017;38(10):1267-1268.