Clostridium difficile infection increases a patient's length of stay in a hospital by an average of six days, according to a study of data from a Canadian hospital.

C. difficile is the most common cause of infectious diarrhea in-hospital, according to background information in the study, and an estimated 10% of patients who become infected in-hospital will die.

For the study, which appeared Monday on the website of the Canadian Medical Association Journal, researchers used the Ottawa Hospital Data Warehouse to analyze data on 136,877 admissions to The Ottawa Hospital between July 1, 2002, and March 31, 2009.

A total of 1,393 patients acquired C. difficile during this time, and these patients spent 34 days in the hospital compared with eight days for patients who did not have the infection. However, the researchers found that patients who became infected with C. difficile tended to have more serious illnesses and would have been more likely to remain longer anyway. When they controlled for the level of illness using a mathematical model, they found that hospital-acquired C. difficile increased the length of stay by six days.

"We believe our study provides the most accurate measure yet of the impact of hospital-acquired C. difficile on hospital length of stay," said lead author Alan Forster, MD, FRCPC, a senior scientist at the Ottawa Hospital Research Institute and associate professor at the University of Ottawa. "C. difficile is a very serious problem for patients and for the healthcare system."

In a related commentary, Dr. David Enoch, of Peterborough and Stamford Hospitals in the United Kingdom, and a coauthor wrote that prevention and strict control measures are key to controlling the spread of the disease: "Adhering to basic evidence-based precautions can rapidly reduce the transmission of C. difficile and its associated mortality. Surveillance is essential to assess the efficacy of interventions."

To download a PDF of the study, visit http://bit.ly/svzJaE.