Fig. 4

Effect of disease activity and ACPA on the gut microbiome in patients with RA. A, B Comparison of gut microbiome composition according to disease activity at the time of stool collection. Remission (DAS28 ≤ 2.6), low disease activity (LDA: 2.6 < DAS28 ≤ 3.2), moderate disease activity (MDA: 3.2 < DAS28 ≤ 5.1), and high disease activity (HDA: DAS28 > 5.1). α-Diversity (shown as the Chao1, Shannon index, and Simpson’s index) (A) and PCoA plot at the OTU level (B). C, D Comparison of gut microbiome composition between ACPA-positive and ACPA-negative RA patients. α-Diversity (shown as Chao1, Shannon index, and Simpson’s index) (C) and PCoA plots at the OTU level (D)