How Antibiotics Increase Rheumatoid Arthritis Risk

There’s a chance antibiotics might increase the risk of rheumatoid arthritis (RA) by altering the gut microbiota that flourishes in our intestines.

This dismaying finding was conveyed in a published study that investigated the association between antibiotic prescriptions and the onset of RA. The study, published in the journal, BMC Medicine, was conducted at the Quadram Institute on the Norwich Research Park in the United Kingdom.

The results of analyzing data from the U.K.’s primary care Clinical Practice Research Datalink revealed that the average odds of developing RA were 60 percent higher for people that had received antibiotics.

More specifically, the study showed people receiving a prescription for one treatment with antibiotics had 40 percent higher odds of developing RA. Worse, those that took two treatments had 66 percent higher odds. The odds were much higher among people who took three or four courses.

The study also found people who had taken antibiotics over the past one to two years had 80 percent higher odds of developing RA. More disturbingly, antibiotics taken five to 10 years ago had an association with 48 percent higher odds.

RA is a long-term, progressive and disabling autoimmune disease of the joints and other body organs. It causes inflammation, swelling and pain. RA usually affects the hands and feet first, but can occur in any joint. It’s also an autoimmune disease, meaning it can affect the entire body.

The study also revealed antibiotics for upper respiratory tract infections (UTIs) had a stronger association with RA. Researchers, however, didn’t identify this link in untreated cases. This seems to suggest it was the antibiotics that raised the risk.

"Antibiotic prescriptions are associated with a higher risk of RA," the study said. "This may be due to microbiota disturbances or underlying infections driving risk.”

The study is another glimpse into the complexity of RA and opens the door for future work in this area, noted the study.

"The more we learn about the complexity of the microbiome and how factors including antibiotics impact these diverse microbial ecosystems, the more insights we have into how this may alter key health outcomes,” Lindsay Hall, group leader and corresponding author of the new study, said.

Hall and her colleagues began from the observation using antibiotics, especially in childhood, significantly raises the risk of developing infections and inflammatory bowel conditions.

Recent studies support this contention. They suggest antibiotics could also increase the risk of autoimmune conditions such as type 1 diabetes, autoimmune liver disease and juvenile idiopathic arthritis.

These diseases suggest the microbiota plays an important role in the development of RA. Hall and the team set out to "investigate the association between antibiotic prescriptions and the onset of RA using a large, U.K. based" dataset.