Faculty Bibliography

OBJECTIVE.: To profile the subgingival oral microbiota abundance and diversity in never-treated, new-onset rheumatoid arthritis (NORA) patients. METHODS.: Periodontal disease (PD) status, clinical activity and sociodemographic factors were determined in patients with NORA, chronic RA (CRA) and healthy subjects. Massively parallel pyrosequencing was used to compare the composition of subgingival microbiota and establish correlations between presence/abundance of bacteria and disease phenotypes. Anti-P. gingivalis antibodies were tested to assess prior exposure. RESULTS.: The more advanced forms of periodontitis are already present at disease onset in NORA patients. The subgingival microbiota of NORA is distinct from controls. In most cases, however, these differences can be attributed to PD severity and are not inherent to RA. The presence and abundance of P. gingivalis is directly associated with PD severity as well, is not unique to RA, and does not correlate with anti-citrullinated peptide antibody (ACPA) titers. Overall exposure to P. gingivalis is similar in RA and controls, observed in 78.4% and 83.3%, respectively. Anaeroglobus geminatus correlated with ACPA/RF presence. Prevotella and Leptotrichia species are the only characteristic taxa in the NORA group irrespective of PD status. CONCLUSIONS.: NORA patients exhibit a high prevalence of PD at disease onset, despite their young age and paucity of smoking history. The subgingival microbiota of NORA patients is similar to CRA and healthy subjects of comparable PD severity. Although colonization with P. gingivalis correlates with PD severity, overall exposure is similar among groups. The role of A. geminatus and Prevotella/Leptotrichia species in this process merits further study.