A new study suggests antibiotic use in people over 60 may be linked to an increased risk of inflammatory bowel disease (IBD).

The study, which will be presented at the upcoming Digestive Disease Week conference, to be held May 21 through 24, found that, in a cohort of more than 2.3 million adults ages 60 to 90, any antibiotic use was associated with a 64% increase in developing ulcerative colitis and Crohn's disease—the primary components of IBD. The risk rose with each additional dose of antibiotics.

The lead author of the study said at a DDW media briefing that people over 60 are one of the most rapidly growing populations of patients with IBD, for reasons that are unclear. While antibiotics, along with genetics and family history, have been linked to IBD risk in younger populations, no studies have looked at the connection in older adults.

"It's quite important to really understand what's driving this," said Adam Faye, MD, MS, of New York University Langone School of Medicine. "There's clearly something in the environment that's driving this new onset of older-onset IBD."