Antibiotic use may drive Clostridium difficile transmission within long-term care facilities, according to the results of a recent study published in Annals of Internal Medicine.
Dr. Kevin A. Brown of Public Health Ontario in Toronto, and his coauthors, assessed long-term care–onset C. difficile infection in the largest and most comprehensive study of its kind to date. The retrospective study included 86 Veterans Health Administration health care regions and examined long-term care residents from January 2006 through December 2012. Study results indicated large variations in regional rates of C. difficile infection, regional antibiotic use, and importation of cases of acute care C. difficile infection (Ann Intern Med. 2016 Apr 19. doi: 10.7326/M15-1754 ).
The total study population included 6,012 cases with a C. difficile infection incidence of 3.7 cases per 10,000 resident days. The regional variability in the incidence of long-term care–onset C. difficile infection was found to be attributable in large part (75%) to antibiotic use and importation from acute care facilities. The data also showed that regional differences in both the prescription of antibiotics and the individual receipt of antibiotics contributed to resident risk, suggesting increased risk for both acquiring and spreading C. difficile.
A potential mechanism offered by the authors for the transmission of C. difficile in facilities with high antibiotic use may be the increased prevalence of residents with asymptomatic C. difficile colonization who become more effective at shedding C. difficile spores when exposed to antibiotics.
Dr. Brown and his colleagues said that efforts designed to reduce C. difficile infection in long-term care should focus on the reduction of total antibiotic use, and that infection control teams may need to take special measures in long-term care facilities that receive residents from hospitals with elevated rates of C. difficile infection.
This study was funded by the U.S. Department of Veterans Affairs and the Centers for Disease Control and Prevention. Dr. Brown reported grants from AstraZeneca outside the submitted work, and another coauthor disclosed grant support from the funding source during the conduct of the study. The remaining coauthors disclosed no conflicts of interest.
