Inflammatory bowel disease (IBD) impacts the digestive tract, type 1 diabetes destroys the insulin-producing cells in the pancreas, and rheumatoid arthritis (RA) causes joint pain and deformity. These three conditions might not seem like they have a lot in common, but they’re all types of autoimmune diseases, and a recent study suggests that if you start with IBD or type 1 diabetes you have a higher than average risk of getting rheumatoid arthritis, too.
The study, which was presented at the annual European Congress of Rheumatology (EULAR 2019) in Madrid, relied on data from a biobank that contains information about 821 people with RA plus an equal number of people who do not have RA. Participants in the study were surveyed and asked to report whether they had been diagnosed with one or more of 77 different conditions and, if so, when.
Experts already know that autoimmune disorders often overlap — about 25 percent of people who have one autoimmune disease later develop at least one more — but this study specifically found a close link between RA and IBD (which includes Crohn’s disease and ulcerative colitis) and type 1 diabetes. Researchers determined that RA patients were significantly more likely than those without RA to also have IBD or type 1 diabetes, and that they were diagnosed with these diseases prior to developing RA.
Although this study doesn’t prove that having IBD or type 1 diabetes causes RA, researchers are intrigued by the timeline of these diagnoses.
“While it is common for patients to have both type 1 diabetes and rheumatoid arthritis, our results suggest that inflammatory bowel disease and type 1 diabetes may predispose to rheumatoid arthritis development, which merits further study,” lead study author Vanessa Kronzer, MD, of the Mayo Clinic School of Graduate Medical Education in Minnesota, said in a press release.