The Microbiome’s Impact on Rheumatoid Arthritis & Drug Response

Dr. Rooney shared work from his lab on individuals at risk of full-blown RA due to their ACPA positivity or arthralgia symptoms (without clinical synovitis). These individuals displayed a distinct microbiome, with decreased diversity of microbiome species. This was true whether or not they eventually progressed to RA as defined by current clinical guidelines. For those who did progress, the gut environment became more unstable in the 10 months preceding full-blown RA, with increased numbers of some species, including certain strains of Prevotellaccae bacteria.^12-13

Such work might eventually lead to interventions in the microbiome to help prevent or delay RA onset in at-risk groups, such as specific dietary changes, prebiotics, probiotics or even fecal microbiota transplantation.¹⁴

Dr. Rooney also discussed a qualitative study that explored attitudes about preventative interventions in people at risk for RA. At present, established modifiable risk factors are somewhat scarce, primarily focused on increasing physical activity, reducing obesity and encouraging smoking cessation.¹⁵

“This gives a potential for a new modifiable risk factor, and it’s been met with great enthusiasm,” said Dr. Rooney.

Ruth Jessen Hickman, MD, a graduate of the Indiana University School of Medicine, is a medical and science writer in Bloomington, Ind.

References

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