According to a review, the more antibiotic prescriptions that individuals 60 and older received, the higher their risk was of developing inflammatory bowel disease, which suggests antibiotic use to be an explanation for some of the increase in cases of ulcerative colitis and Crohn’s disease in older individuals.
The researchers believe that environmental factors are more significant than genetics in older individuals. There’s typically a dominant family history in younger individuals with a new diagnosis of ulcerative colitis and Crohn’s disease, but that’s not the case in older individuals.
The researchers reviewed patient prescribing records for 2.3 million individuals aged 60 and older who had been newly diagnosed with inflammatory bowel disease.
The study examined how many courses of antibiotics had been prescribed, and how recently the prescriptions were relative to the diagnosis and specific antibiotic classes used.
The study revealed that any use of antibiotics was linked to higher inflammatory bowel disease rates, with the risk significantly increased with each antibiotic course. Individuals were 27% more likely to receive an inflammatory bowel disease diagnosis after 1 prescription compared to individuals who had not used antibiotics.
With 2 courses, the risk increased by 55% and with 3 courses it increased by 67%. With 4 courses, the risk increased by 96%; and with 5 or more, individuals were 236% more likely to be diagnosed with inflammatory bowel disease compared to individuals with no antibiotic use in the past 5 years.
New diagnoses of inflammatory bowel disease were highest if antibiotics had been prescribed 1 to 2 years before, and the risk stayed high for prescriptions in the period 2 to 5 years prior to diagnosis.
The association was found for all kinds of antibiotics besides nitrofurantoin, which is typically prescribed for infections of the urinary tract.
Normally prescribed antibiotics for gastrointestinal infections had the highest chance of being linked to a new diagnosis of inflammatory bowel disease.
Antibiotics prescribed less than a year prior to diagnosis were omitted from the study to lessen the chance that the prescriptions had been for gastrointestinal disease symptoms that had not been diagnosed yet.