ACPA-negative obese RA patients tended to have higher TJC (IRR1.22; 95% CI: 0.96, 1.55) and VAS (β4.3; 95% CI: − 0.4, 9.0), while SJC (IRR1.07; 95% CI:0.85, 1.33) and CRP (β0.24; 95% CI: − 1.29, 3.32) were unaffected. This evidence concerns the gene CRP and rheumatoid arthritis.