Multiple-Bed Rooms Add No Risk to C Difficile Infection Spread

Alon Vaisman, MD

Patients inside multiple-bed rooms in general medicine and surgical wards are not at higher risk of Clostridium difficile infection, according to a recent study.

Investigators from California observed adult general medical and surgical patients at San Francisco General Hospital and Trauma Center in order to determine whether assignments to a multiple-bed room increased their risk of hospital-onset C difficile infection. Between January 2010 and December 2015, the investigators studied the effect of the multiple-bed room exposure at admission and at symptom onset. They also collected data about the relationship between room assignment—patients residing in a single-bed room compared with multiple-bed rooms—and the development of C difficile infection.

Originally, the study authors expected that assigning C difficile carriers to single-bed rooms upon their admission would reduce overall rates of C difficile infection, that single-bed room admission would protect everyone else, study author Alon Vaisman, MD explained to MD Magazine® as previous literature had indicated as much. Furthermore, it seemed intuitive that by reducing exposure of patients—high-risk patients and otherwise—to other hospitalized patients, the hospital could protect against hospital-acquired infections.

Ultimately, the investigators discovered 187 cases that they matched with 512 and 515 controls for admission and symptom onset analyses, respectively. The risk associated with the development of C difficile infection and multiple-bed room exposure during 7 and 14 days prior to diagnosis were 1.08 and 0.96, respectively. According to the study authors, there was no significant relationship between the first 7 and 14 days after admission or among patients with Charlson comorbidity scores of 4 or more in either cohort.

“One possible reason we had a null result was that patients who developed [hospital-onset C difficile infection] carried the organism from the community on admission and therefore room assignment could not modify their risk of developing diarrhea,” Vaisman said.

Alternatively, Vaisman explained that, “patients in single rooms occupy beds that were more likely to have patients who previously had C difficile infection, which is a known risk factor for [hospital-onset C difficile infection]; however, patients in single-bed rooms are also more likely to have health care workers entering their rooms perform better hand hygiene, have less overall traffic, less introduction of potentially infected equipment, etc. Thus, these 2 effects may have cancelled each other out, although it is unclear because our study did not address these mechanisms. This hypothesis could be tested in the future to assess why multi-bed room exposure may be associated with increased risk of C difficile infection.”

Their study did not address this though, and more research is required with both larger cohorts and multiple sites to definitively prove this theory. The investigators said that their research could impact future inpatient room assignments and even hospital design down the road.

There still could be an argument for isolating just carriers for C difficile infection, said Vaisman, but again, the study did not address that possibility.

“In parts of North America where hospital budgets allow for all-private room designs, our study will not change the management of admissions and bed flow,” Vaismon added. “However, in areas where budgets are limited (such as in public systems), this study lends a small amount of evidence to the lack of benefit to having all-single private room designs. This, of course, must be weighed against all the other advantages of single rooms, such as patient privacy, reduced exposure to other pathogens, and patient satisfaction.”

The study, “Examining the association between hospital-onset Clostridium difficile infection and multiple-bed room exposure: a case-control study,” was published in Infection Control & Hospital Epidemiology.