I-FABP levels were significantly higher in RA patients compared to HCs (507 pg/mL [371–779] vs 301 pg/mL [176–437], respectively; p = 0.04), even after adjustment for BMI (p = 0.039) or both BMI and HLA status (p = 0.047) (Fig. 2d). Here, FABP2 is linked to rheumatoid arthritis.