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Residents of nursing homes with high antibiotic use are at higher risk of antibiotic-related adverse events


Residents of high antibiotic use homes have a 24 per cent higher risk of antibiotic-related adverse events according to a new study by researchers at the Institute for Clinical Evaluative Sciences (ICES). The study also found antibiotic use varied 10-fold in nursing homes across Ontario.

“Our findings show that these adverse outcomes affected not only residents who directly received antibiotics, but also those residents who did not directly receive antibiotics because infections like Clostridium difficile and antibiotic resistant bacteria can be transmitted between patients,” said lead author Dr. Nick Daneman, an adjunct scientist at ICES.

The study of more than 100,000 residents living at more than 600 nursing homes in Ontario between January 2010 and December 2011 found a 10-fold variability in antibiotic use from as low as 20 to as high as 200 antibiotic days per 1,000 resident days. 

Antibiotics are the most commonly prescribed medications among nursing home residents, with about two-thirds of residents receiving antibiotic treatment each year.

Adverse antibiotic-related events (such as allergic reactions, general medication adverse events, Clostridium difficile infection, diarrhea and antibiotic resistant bacteria) were more common in residents of high antibiotic use nursing homes (affecting 13.3 per cent of residents) as compared to low antibiotic use nursing homes (affecting 11.4 per cent of residents). 

After accounting for nursing home factors and resident risk factors, living in a high versus low antibiotic use nursing home was associated with a 24 per cent increased risk of a resident experiencing an antibiotic-related adverse event. 

“Our findings suggest that improved antibiotic stewardship within nursing homes could potentially improve the safety of all nursing home residents,” added Daneman.

“Variability in antibiotic use across nursing homes and the risk of antibiotic-related adverse outcomes for individual residents,” was published today in JAMA Internal Medicine.

Authors:  Daneman N,  Bronskill SE, Gruneir A, Newman A, Fischer HD, Rochon PA, Anderson GM, Bell CM.

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.

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