May 13 (UPI) -- The risk for inflammatory bowel disease among adults age 60 and older rises with the number of antibiotics they are prescribed, a study presented Friday found.
After receiving one antibiotic prescription, older adults are 27% more likely than those with no antibiotic use within the past five years to be diagnosed with inflammatory bowel disease, or IBD, data presented during the Digestive Disease Week annual conference showed.
Those who have been prescribed antibiotics twice have a 55% higher IBD risk, while those given the drugs used to treat infections three times have a 67% higher risk. After four prescribed antibiotic courses, IBD risk increases by 96%, while it rises 236% after five courses, researchers said.
However, "if patients are coming in with clear infections, and they need antibiotics, they should not be withheld because of these findings," study co-author Dr. Adam S. Faye said in a press release.
"Avoiding antibiotics at all costs is not the right answer," said Faye, an assistant professor of medicine and population health at NYU Grossman School of Medicine in New York City.
IBD actually is a group of diseases that includes Crohn's disease and ulcerative colitis, according to the Centers for Disease Control and Prevention.
All of the IBD diseases are caused by chronic inflammation of the gastrointestinal tract that leads to damage, resulting in pain and discomfort, the agency says.
About 3 million adults in the United States have been diagnosed with IBD, it estimates.
Most cases of IBD occur in people who have a family history of the disease, but some are attributed to diet and other "environmental" exposures, including drugs used to treat other health conditions, Faye and his colleagues said.
Previous research indicates antibiotics and other drugs may alter the gut microbiome, the bacteria in the gastrointestinal tract that helps the body digest and process food.
"In older adults, we think that environmental factors are more important than genetics," Faye said.
The findings of this study are based on a review of 2.3 million patient records contained in Denmark's national health database.
Faye and his colleagues reviewed prescribing records for people age 60 years and older who were newly diagnosed with inflammatory bowel disease between 2000 and 2018.
They also recorded the number of courses of antibiotics prescribed, how recently they had been prescribed in relation to the diagnosis and specific classes of antibiotics used, they said.
New IBD diagnoses were highest among study participants when antibiotics were prescribed one to two years before, but the risk remained elevated for prescriptions in the period two to five years before diagnosis, the data showed.
Antibiotics usually prescribed for gastrointestinal infections were the most likely to be associated with a new IBD diagnosis, the researchers said.
Based on the findings, older adults with new gastroenterological symptoms should be evaluated for IBD in they have a history of recent antibiotic prescriptions, they said.
"When you look at younger patients with new diagnoses of Crohn's disease and ulcerative colitis, there's generally a strong family history," Faye said.
"But that is not the case in older adults, so it's really something in the environment that is triggering it," he said.
