While antibiotics have been associated with the development of inflammatory bowel disease (IBD), data regarding this association in individuals with older-onset IBD is lacking. Older adults are the fastest growing IBD subpopulations with 15% of those diagnosed being 60 years or older. While younger patients with a new diagnosis often have a strong family history of IBD, “in older adults, it seems that something in the environment is triggering it,” Adam Faye, MD, said in a media briefing preceding Digestive Disease Week, on May 12, 2022.

Dr Faye is an assistant professor of medicine and population health at NYU Grossman School of Medicine.

In this study, Dr Faye and colleagues observed a cohort of individuals from the Denmark national registry who were aged 60 years or older and had not received a previous diagnosis of diagnosis, from 2000-2018. The incidence rate ratios calculated assessed antibiotic exposure 1-5 years before diagnosis and took into consideration the number of courses, the timing of courses, and the specific classes of antibiotics used. This cohort included 2,327,796 individuals with 22,670,484 years of follow-up. There were 10,773 new diagnoses of ulcerative colitis and 3,825 of Crohn disease.

Researchers found that antibiotic exposure was associated with an increased risk of IBD; the risk was higher in those individuals who received more courses of antibiotics, and in those who received antibiotics 1 to 2 years prior to their diagnosis. The risk persisted even beyond this time to those who received antibiotics 5 to 10 years prior to diagnosis. A higher risk of IBD was also associated with antibiotics targeting gastrointestinal pathogens. Antibiotics with a minimal impact on gastrointestinal microbiome, such as nitrofurantoin, did not increase the risk of older-onset IBD.

Dr Faye concluded, “If you know that patients have taken courses of antibiotics recently, perhaps IBD moves a bit higher on your differential.” He added that an underlying infection, which prompted the antibiotic use, may also contributed to the development of IBD; future microbiome studies could help in distinguishing between the 2, he noted.

—Allison Casey

References:
Faye AS. Antibiotics as a risk factor for older-onset IBD: Population-based cohort study. Presented at: DDW Media Briefing; May 12, 2022; Virtual.

Antibiotics Increase the Risk of IBD in Older Adults. Meeting News. DDW/AASLD. May 16, 2022.