Study sheds light on how providers can better coordinate and share information
Patient sharing‚Äîin which individuals¬† are transferred from one hospital to another or when patients seek treatment at different hospitals on their own‚Äîis nine times as pervasive as previously thought, according to the first study to look at the phenomenon in-depth. This gross underestimation may have implications for controlling the spread of infectious diseases among hospitals.
"Hospitals share large numbers of patients without knowing it," says Susan Huang, M.D., director of epidemiology and infection prevention at the University of California, Irvine. Her study looked at 240,000 admissions, including direct and indirect transfers among all 31 hospitals in Orange County, Calif. She presented her findings at the annual meeting of the Society for Healthcare Epidemiology of America in March.
Huang found that only one in nine shared patients are transferred directly between hospitals. Most are discharged, then readmitted
"Currently, hospitals operate as isolated entities, without understanding how actions and interventions might impact other facilities," Huang says. By understanding the magnitude of patient sharing, they might cooperate in preventing the spread of infectious diseases. Her research might be especially relevant for diseases with substantial incubation periods or prolonged carrier states, such as methicillin-resistant Staphylococcus aureus or vancomycin-resistant enterococcus, because patients often don't exhibit symptoms until after discharge.
"How patient sharing contributes to the problem of health care-associated infections and antimicrobial resistance is something we need to understand better," says John Jernigan, M.D., a medical epidemiologist at the Centers for Disease Control and Prevention, Atlanta, adding that infectious disease surveillance among hospitals is usually institution-based. When a patient goes from hospital A to nursing home B to hospital C, each facility may perform disease surveillance only while the patient is admitted.
"If those systems don't talk to each other, it's hard to make much sense of the data," Jernigan says.
Frank Lowy, M.D., director of infectious diseases at Columbia University, New York, says the true value of the study may not be known until a specific pathogen is tested within this context. "It will be interesting to see whether along with increased frequency of patient migration there's increased risk of transfer of antibiotic-resistant bugs," he says.
If there is, electronic medical records may be one solution. In France, for instance, every citizen is given a carte vitale, a credit card-sized device containing personal medical information. Warnings could be added to such cards on discharge from a hospital specifying whether patients carry agents such as MRSA or VRE.
"This would alert admitting offices that these patients might need to be isolated until they are culture-negative," Lowy says.