However, Hb levels were significantly lower (12.8 ± 1.51 (12.8) vs. 13.5 ± 0.38 (13.6) g/dL, p = 0.001), while inflammatory markers, CRP (13.7 ± 20.3 (7.18) vs. 4.57 ± 1.30 (4.0) mg/L, p = 0.004) and ESR (30.1 ± 18.4 (29) vs. 16.7 ± 3.55 (16) mm/h, p < 0.001), were significantly higher in the RA group compared with controls. This evidence concerns the gene GSTM1 and rheumatoid arthritis.