Background/Purpose: Patients with rheumatoid arthritis (RA) have accelerated cardiovascular disease independent of traditional risk factors. Previous studies demonstrate that the gut microbiome is altered in patients with RA and that the gut microbiota may play a role in development of cardiovascular disease in the general population. We tested the hypothesis that gut dysbiosis is associated with early vascular dysfunction in patients with RA.

Methods: Patients with RA (N=30) and control subjects (N=30), frequency matched for age, race and sex were recruited from the Nashville VA hospital and Vanderbilt University Medical Center. Measures of early vascular function including augmentation index, carotid-radial pulse wave velocity, and reactive hyperemia index as well as clinical data were obtained. Stool 16S rRNA gene sequencing was performed by Corebiome. The gut microbiome composition was compared in RA and control subjects with adjustment for false discovery rate. The primary analyses were determination of the association between alpha diversity (as a summary statistic of dysbiosis) and vascular measures in RA. Exploratory analyses included the association of phylum level relative abundance of microbes with vascular measures in RA.

Results: After adjustment for false discovery rate, there was no significant difference in gut microbiome composition, and a non-significant decrease in alpha diversity in RA versus control subjects. Among patients with RA, higher augmentation index and pulse wave velocity (both indicating increased vascular stiffness) were associated with lower alpha diversity (indicating increased dysbiosis) (Figure 1). However, these associations were not present among control subjects; and disease status (RA versus control) modified the association between Shannon index and augmentation index (P=0.03 for interaction, Figure 2). Among patients with RA higher augmentation index was associated with significantly greater proportion of gut Proteobacteria and lower proportion of Verrucomicrobia; and higher PVW was associated with less Euryarchaeota (Figure 1). Similarly, higher RA disease activity was associated with lower alpha diversity, significantly lower proportion of Euryarchaeota and more Fusobacteria in the gut (Figure 1).

Conclusion: Among patients with RA, but not control subjects, reduced gut microbiome alpha diversity was associated with increased vascular stiffness. Gut microbiome dysbiosis may be a contributor to accelerated atherosclerosis in RA.

Figure 1

Figure 2

« Back to 2019 ACR/ARP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/gut-dysbiosis-is-associated-with-measures-of-early-vascular-dysfunction-in-patients-with-rheumatoid-arthritis/