AB1046 Could serum tweak level be an indicator of subclinical atherosclerosis in rheumatoid arthritis?

Abstract

Background TWEAK is a type 2 transmembrane glycoprotein of TNF family that has multiple functions such as angiogenesis, regulation of tissue production-destruction, proinflammatory cytokine release. TWEAK and Fn14 receptor interaction has an important role in pathogenesis of atherosclerosis. Our aim was to evaluate subclinical atherosclerosis and its association with serum sTWEAK, Fn14 and CD163 levels in RA patients. Methods One hundred Rheumatoid Arthritis (RA), 50 Spondyloarthritis (SpA) patients and 50 healthy controls (HC) were included in the study. Serum soluble TWEAK, CD163 and Fn14 levels were measured by ELISA tecnique. Subclinical atherosclerosis was evaluated by echocardiography, which includes carotis intima media thickness (cIMT), aortic strain, stiffness and elasticity. Results In RA group 73 (73%) patients were using DMARD's and 27 (27%) were biological drugs, the mean DAS28 score was 3.49±1.31. At the end of the study, TWEAK levels were found significantly lower (RA; 942.4±305.9, AS; 1087.2±311.0 and HC; 1061.3±402.8 pg/ml, p=0.05), and Fn14 levels were significantly higher (RA; 509.4±861.4, AS; 163.5±249.0 and HC; 91.5±67.9 pg/ml, p<0.01) in RA patients compare to both groups. In addition Fn14 levels were higher in RA patients using biological drugs and seropositive subgroups (1042±1363 vs. 312±451 pg/ml, p<0.01 and 674±101 vs. 188±236 pg/ml, respectively, p<0.01). Fn14 levels were correlated with disease duration (r=0.38, p<0.01). CD163 levels were similar in all groups. Although there was not any difference in cIMT measurements among groups, aortic stiffness was increased (p=0.03), aortic strain and elasticity were decreased (p=0.03, p=0.02) in RA patients compare to healthy controls. Multivariate analysis showed cardiovascular parameters were only associated with age. Conclusions In this study we observed impaired aortic parameters showing subclinic atherosclerosis in RA patients. At the same time, decreased levels of serum sTWEAK and elevated levels of serum sFn14, were also shown in RA group. The difference in levels of serum soluble form of these biomarkers may be related to vascular damage in our RA patients who have low disease activity. However, further studies are needed to demonstrate association between atherosclerosis and these biomarkers in RA patients. Disclosure of Interest None declared