The more roommates you have during a hospital stay, the greater your risk of acquiring a dangerous infectious disease such as Clostridium difficile, according to new Canadian research.
The study, published in the American Journal of Infection Control, shows that each roommate a patient is exposed to hikes his or her risk of infection by 10 per cent.
"That is a significant risk," Dick Zoutman, a professor of community health and epidemiology at Queen's University in Kingston, Ont., said in an interview. He noted that, in Canada, most hospital rooms have either two or four beds and "there is a lot of turnover," meaning that patients are routinely and unnecessarily exposed to a lot of infectious diseases.
Dr. Zoutman said that the research provides powerful evidence that single rooms are the safest, and should be the norm. "The take-home message is that our hospitals should be designed with private rooms for everyone," he said.
While there would be an up-front cost, Dr. Zoutman noted that, over the long-term, savings would be substantial: "This research provides the direct proof that should settle the discussion about the need for private rooms."
Earlier research showed that about 225,000 patients a year suffer from hospital-acquired infections that substantially extend their stays, and between 8,000 and 12,000 people die annually as a result. infection 4
The new study was conducted at Kingston General Hospital, which has 451 in-patient beds and about 17,000 patients a year. There are 107 single-occupancy rooms, 83 double-occupancy, six triple-occupancy and 19 quadruple-occupancy, plus open bay areas and specialized units such as intensive care.
The study, which began as a master's thesis by Queen's student Meghan Hamel, examined patient records from 2001 to 2006. The research team looked for patients who suffered from three common but dangerous infections - C. difficile, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) - and examined those patients' exposure to other patients.
For each roommate to whom a patient was exposed, the risk of contracting C. difficile increased 11 per cent; for MRSA, 10 per cent, for VRE, 15 per cent.
The median number of roommates was just over two, but some patients had as many as 46 roommates, whether due to a lengthy stay or to a heavy rotation of roommates.
Dr. Zoutman, who is also head of infection control at Kingston General, said that although the research was conducted at only one institution, "it is pretty typical of a Canadian hospital, and there is no reason to think this situation doesn't exist everywhere."
The infections that were studied - C. difficile, MRSA and VRE - are not airborne, but spread by contact.
Dr. Zoutman said the likely reason that roommates increase the risk of infection is that patients share a washroom. (The mantra in infection control is: One bum per toilet.) Another likely explanation involves inadequate handwashing by patients and health professionals alike; doctors sometimes don't wash their hands between patient visits in a single room.
"The goal should be private rooms, or at the least, semi-private rooms," Dr. Zoutman said. "But in the meantime, there are things we can do: We should be cleaning our hands, and we should really scrutinize how we clean our hospitals."
André Picard