Do bacteria in the mouth affect arthritis risk?

A new study from the Netherlands found that people at risk of developing rheumatoid arthritis (RA) and people with early RA (ERA) had higher levels of two groups of bacteria, Prevotella and Veillonella, in their saliva.
Both groups also had higher levels of Veillonella in the bacterial coating of their tongue.
Prevotella and Veillonella are potentially pro-inflammatory bacteria, and their relative abundance suggests a possible link between oral microbes and RA.
This study builds on previous research that found that people with ERA, at risk of developing RA, and with diagnosed RA tend to experience higher rates of periodontal disease and changes in their oral and intestinal microbiota.
If confirmed, these findings could help illuminate how RA develops and improve preclinical testing for RA and ERA.