HOLLYWOOD, FLA. – Exposure to antibiotics other than penicillins, in particular metronidazole and quinolones, was associated with new-onset Crohn’s disease, based on a meta-analysis of observational and case-control studies presented by Dr. Ryan Ungaro at a conference on inflammatory bowel diseases.
"Exposure to antibiotics may somehow contribute to alterations in the microbiome and result in dysbiosis, which is known to be part of the pathogenesis that leads to IBD," said Dr. Ungaro, of the Icahn School of Medicine at Mount Sinai, New York. Alternatively, antibiotic exposures might just be surrogate markers for an infectious trigger that is actually associated with IBD. The analysis did not detect a link between antibiotic exposure and ulcerative colitis.
Whitney McKnight/Frontline Medical News
Dr. Ryan Ungaro
Dr. Ungaro and his colleagues performed a meta-analysis of 11 studies that included the records of 7,208 patients who had been newly diagnosed with IBD after antibiotic exposure; 3,937 had Crohn’s disease, 3,207 had ulcerative colitis, and 64 had unclassified IBD. Nine of the studies accounted for the potential confounding of diagnostic delay, with a range of 4 months to 4 years.
All classes of antibiotics except penicillin were implicated in new-onset IBD, with an odds ratio (OR) of 1.55 for the overall risk of new-onset IBD after antibiotic exposure. Three studies provided data on the use of metronidazole, which proved to have the highest associated risk for new cases of IBD with a pooled OR of 5.01 (P = .005). Quinolones were accounted for in three of the studies and carried the next-highest associated risk, an OR of 1.79 (P = .040).
When stratified by age, the OR for new IBD diagnosis in adults was 1.43 and in children was 1.89. The OR for a new diagnosis of Crohn’s disease was 1.56 in adults and 2.7 in children.
The conference was sponsored by the Crohn’s & Colitis Foundation of America.
Dr. Ungaro did not have any relevant disclosures.