Omentin concentrations are independently associated with those of matrix metalloproteinase-3 in patients with mild but not severe rheumatoid arthritis

Omentin is an adipokine that reportedly protects against cardiometabolic risk. We investigated the relationships between omentin concentrations and subclinical cardiovascular disease in rheumatoid arthritis (RA). Omentin concentrations were measured in 213 (104 black; 109 white) RA patients. Relationships of omentin levels with those of endothelial activation markers, ultrasound determined carotid intima-media thickness and plaque, and matrix metalloproteinase (MMP)-2, -3 and -9 that mediate altered plaque stability, were identified in confounder adjusted multivariate regression models. Omentin concentrations were inversely associated with MMP-3 levels [β = -364 (0.113), p = 0.002]. This relationship was influenced by population origin, RA activity and the erythrocyte sedimentation rate and joint deformity count (interaction p value = 0.009, 0.04, 0.04 and 0.007, respectively). Accordingly, the omentin-MMP-3 concentration relationship was reproduced in white [β (SE) = -0.450 (0.153), p = 0.0004)] but not black patients [β (SE) = -0.099 (0.195), p = 0.6)], in participants with disease remission or mild disease activity [β (SE) = -0.411 (0.139), p = 0.004] but not with moderate or severe RA activity [β (SE) = -0.286 (0.202), p = 0.2], and in those with a small [β (SE) = -0.534 (0.161), p = 0.001] but not large erythrocyte sedimentation rate [-0.212 (0.168), p = 0.2] and without [β (SE) = -0.554 (0.165), p = 0.0001] but not with large joint deformity counts [-0.110 (0.173), p = 0.5]. Omentin levels were unrelated to endothelial activation and atherosclerosis. Among patients with RA, a lack of plaque stabilizing effects by omentin may contribute to the reported link between severe disease and increased cardiovascular risk. The association between concentrations of omentin and MMP-3 is population specific in RA.