Analysis of subgingival microbiome of periodontal disease and rheumatoid arthritis in Chinese: A case-control study

OBJECTIVE: Periodontitis (PD) and rheumatoid arthritis (RA) share similar pathogenesis. Evidences indicated that oral bacteria play an important role in the etiology of both diseases. For example, Porphyromonas gingvialis connect the two diseases through immune responses. We designed this study to compare bacterial diversity in RA, PD and healthy subjects and to investigate whether there are other oral bacteria play an potential role in linking the two diseases. METHODS: This study included 3 groups of Chinese participants who visited Sichuan Provincial People’s Hospital during August 2018 and March 2019. Subgingival plaques were collected from RA group (n = 54), PD group (n = 45) and normal group (n = 44). Illumina MiSeq was used to compare the composition of subgingival microbiota and analyze correlations between oral bacteria and both diseases. RESULTS: Alpha diversity Analysis reflected similar microbiome profile in RA, PD and healthy groups. But we found Treponema was significantly more abundant in the PD and RA groups than healthy group at each taxonomic level from the phylum down to the genus level. Porphyromonas, Prevotella, and Veilonella were significantly more abundant in RA while Streptococcus, Gemella, Planobacterium were verified the opposite results. CONCLUSIONS: We found no significant group differences referent to either microbial diversity or richness. But we picked out Spirochaetes which may link the two diseases. Upper/lower regulation of some microbia in RA may remind us a direction to explore the role they play in pathogenesis.