In a nonadjusted linear mixed model, we observed a significant effect of anakinra treatment on reduction of HbA1c% after 3 months (β: −0.85, p < 0.001, 95% CI −1.28 to −0.42) and 6 months (β: −1.05, p < 0.001, 95% CI −1.50 to −0.59), and similar results were observed adjusting the model for possible RA and T2D clinical confounders (male sex, age, ACPA positivity, use of CCSs, RA duration, T2D duration, use of oral antidiabetic drug, BMI) after 3 months (β: −1.04, p < 0.001, 95% CI −1.52 to −0.55) and 6 months (β: −1.24, p < 0.001, 95% CI −1.75 to −0.72). This evidence concerns the gene PRTN3 and type 2 diabetes mellitus.