News at Smith

The Latest Reason Why Hospitals Should Limit Antibiotic Use

Apr 07, 2017
World Class Faculty & Research


SMITH BRAIN TRUST – Getting admitted to the hospital means a 1-in-20 chance of contracting an infection, maybe even a potentially deadly antibiotic-resistant bacteria, also referred to as multidrug-resistant organisms (MDROs).

Risk of infection comes with the medical care. The ironic scenario drains billions of dollars yearly from the U.S. healthcare system, and can be medically, emotionally and financially devastating to patients. About 2 million people suffer hospital-acquired infections each year, with at least 23,000 dying as a result.

Modern hospitals are taking precautions. Infection control programs work to minimize the spread of infections, and antibiotic stewardship programs seek to ensure that patients receive the most appropriate antibiotic therapy when antibiotics are needed. These programs are backed by research demonstrating the patient-care and cost benefits.

Now, there’s a new pillar to support the use of such programs. Researchers have quantified the rate at which scaling down antibiotic use reduces MDRO transmission.

"Reducing antibiotic use in intensive care units by even small amounts can significantly decrease transmission of dangerous multidrug-resistant organisms," says Sean Barnes, assistant professor of operations management at the University of Maryland’s Robert H. Smith School of Business and lead author of Impact of Reducing Antibiotics on the Transmission of Multidrug-Resistant Organisms, a study newly published by Infection Control & Hospital Epidemiology.

Barnes developed a model to simulate the interactions between patients and hospital workers, and performed experiments on the effect of reducing antibiotic usage by 10 percent and 25 percent. This simulated intervention led to a reduction in the spread of deadly bacteria by 11.2 percent and 28.3 percent, respectively.

Antibiotics use increases a patient’s infection-susceptibility and likelihood for the bacteria to mutate spontaneously or to mix with other strains to become drug-resistant. These patients can appear symptom-free, or "colonized" in hospitals, where healthcare workers can unknowingly transmit the MDROs from them to other susceptible patients.

"Antibiotic exposure is the most significant driver of resistance. In the hospital setting, nearly 50 percent of all patients receive an antibiotic, including up to 75 percent of all critically ill patients," says Barnes. "But what is really troubling is that nearly half of all antibiotics prescribed may be inappropriate."

Barnes’ coauthor and UMD School of Medicine professor Kerri Thom says that antibiotics have been “one of the most useful and critical drugs in modern medicine, but overuse of these drugs has hurt us by supporting the development of MDROs.”

"Our model suggests that substantial reductions in infection rates are possible if stewardship programs aggressively pursue opportunities to reduce unnecessary usage of antibiotics," Thom adds.

Such opportunities include what the Centers for Disease Control refers to as "broad interventions" for antibiotic stewardship programs. These include antibiotic "time outs" 48 hours after antibiotics are initiated to reassess the continuing need and choice of antibiotics; prior authorization by an "antibiotic expert" of certain types of antibiotic therapies; and "prospective audit and feedback," in which expert staff apart from the treating team externally review antibiotic therapy, especially in critically ill patients and in cases where multiple antibiotics are being used.

However, just 48 percent of hospitals have robust antibiotic stewardship programs as defined by the CDC, says another coauthor of the study, Johns Hopkins School of Medicine professor and epidemiologist Sara Cosgrove.

Speaking at the Society for Healthcare Epidemiology of America Spring 2017 Conference, Cosgrove also noted that few organized antibiotic stewardship activities occur in long-term care or ambulatory settings, and although a national surveillance system for inpatient antibiotic use is currently in place, "there is slow uptake."

"The good news is that emerging national requirements for antibiotic stewardship programs across healthcare are likely to improve how we use antibiotics across the United States," she adds.




About the University of Maryland's Robert H. Smith School of Business

The Robert H. Smith School of Business is an internationally recognized leader in management education and research. One of 12 colleges and schools at the University of Maryland, College Park, the Smith School offers undergraduate, full-time and part-time MBA, executive MBA, online MBA, specialty master's, PhD and executive education programs, as well as outreach services to the corporate community. The school offers its degree, custom and certification programs in learning locations in North America and Asia.