The odds of developing rheumatoid arthritis are 60% higher in individuals exposed to antibiotics than in those not exposed, according to an analysis of medical records.
While the study does not prove that antibiotics cause the autoimmune condition, the odds of developing rheumatoid arthritis increased along with the number of antibiotic treatments received. The type of infection also affected risk, with upper respiratory tract infections having the strongest association. In contrast, the type of antibiotic did not appear to affect outcomes, wrote the United Kingdom-based researchers.
Other studies have also shown associations between antibiotic use and autoimmune conditions, including type 1 diabetes and autoimmune liver disease, the authors reported. In the case of rheumatoid arthritis, they propose the association may be due to disturbances in the body’s microbiota – the organisms that affect the immune system – or to the underlying infections.
“This exciting work offers another glimpse into the complexity of understanding rheumatoid arthritis, opening the door for future work in this area,” said Christian Mallen, Ph.D., Keele University.
Rheumatoid arthritis is likely to be caused by multiple factors, and the researchers do not advise that people stop taking antibiotics when needed.
The study was published in BMC Medicine.