HQ Team
November 10, 2024: Rheumatoid arthritis may be associated with higher amounts of bacteria accumulating in the gut ten months before clinical diagnosis, researchers reveal.
Researchers at the University of Leeds gleaned data from 124 individuals with high levels of cyclic citrullinated peptide antibody (CCP+) — an antibody that attacks healthy cells in the blood — which indicates a risk of developing rheumatoid arthritis.
Initially, the researchers compared their samples to 22 healthy individuals and seven people who had a new rheumatoid arthritis diagnosis. The findings from this larger group showed that the gut microbiome was less diverse in the at-risk group, compared to the healthy control group.
Longitudinal study
In a longitudinal or panel study, researchers repeatedly examined a group of people to detect any changes that might occur over some time. The longer-term study was conducted on 19 patients at risk of rheumatoid arthritis, with samples taken five times during 15 months.
Five of these patients progressed to clinical arthritis, and the research showed they had gut instability with higher amounts of bacteria including Prevotella, which is associated with rheumatoid arthritis, about ten months before progression.
The remaining 14, whose disease didn’t progress, had largely stable amounts of bacteria in their gut.
Rheumatoid arthritis is a chronic autoimmune inflammatory disease associated with disability and premature death. In 2020, an estimated 17·6 million people had rheumatoid arthritis worldwide, according to the Institute for Health Metrics and Evaluation.
Swelling, loss of function
The disease affects the joints and occurs when the immune system, meant to protect the body from infections and disease, attacks its tissues. The disease causes pain, swelling, stiffness, and loss of function in joints.
“Patients at risk of rheumatoid arthritis are already experiencing symptoms such as fatigue and joint pain, and they may know someone in their family who has developed the disease,” said lead researcher Dr Christopher Rooney, NIHR Academic Clinical Lecturer at the University of Leeds.
“As there is no known cure, at-risk patients often feel a sense of hopelessness, or even avoid getting tested. This new research might give us a major opportunity to act sooner to prevent rheumatoid arthritis,” he said.
Earlier research has linked rheumatoid arthritis to the gut microbiome, which is the ecosystem of microbes in your intestines. The new study, published in the Annals of the Rheumatic Diseases, reveals a potential intervention point.
Eating more fibre
Potential treatments that the researchers want to test during the ten-month window include changes to diet like eating more fibre, taking prebiotics or probiotics, and improving dental hygiene to keep harmful bacteria from periodontal disease away from the gut.
Lucy Donaldson, director for research and health intelligence at Versus Arthritis, which funded the study said the exact relationship between gut inflammation and rheumatoid arthritis development remains unclear.
“In a small number of patients within the study, the gut changes occurred before there were any changes to the joints observed by a rheumatologist, but more research is needed to determine whether these influence each other.”
The research was carried out in collaboration with the National Institute for Health Research Leeds Biomedical Research Centre.
