Periodontitis and Oral Bacteria Related to Rheumatoid Arthritis: A Case-Control Study

This study compared periodontal status and oral bacteria between rheumatoid arthritis (RA) patients and healthy controls (HCs), and examined the influence of oral bacteria on the association between periodontitis and RA.

In total, 85 patients with RA and 119 HCs were enrolled. The oral microflora DNA test was used to quantify the oral bacterial species detected in gingival crevicular fluid. Probing depth and the clinical attachment level of the periodontal ligament were taken as parameters of periodontal status. Height, body weight, medical history, family history of RA, lifestyle habits, and stress were evaluated using a self-administered questionnaire. Univariate and multivariate logistic regression analyses were conducted to assess the association between RA and periodontal status/oral bacteria.

RA patients exhibited significantly greater probing depth than HCs. The HCs demonstrated higher abundances of Fusobacterium nucleatum subsp. polymorphum, Fusobacterium periodonticum, Campylobacter showae, Campylobacter gracilis, Eikenella corrodens, Streptococcus mitis, Streptococcus mitis bv 2, and Actinomyces naeslundii II. In forward stepwise multivariate analysis, the odds ratios (ORs) for RA were significantly higher for patients with a family history of RA, smokers, those with deep periodontal pockets, and those with a larger population of F. nucleatum subsp. animalis and Veillonella parvula. Patients with more Campylobacter gracilis had a significantly lower OR for RA.

A comparison of the oral bacteria of RA patients and HCs suggests that F. nucleatum subsp. animalis and V. parvula are involved in RA patients. However, there are still many unknowns about the relationship between oral bacteria and RA, and further research is needed.