A pilot study of endothelial dysfunction and aortic stiffness after interleukin-6 receptor inhibition in rheumatoid arthritis

Interleukin (IL)-6 is a pleiotropic proinflammatory cytokine involved in the pathogenesis of both atherosclerosis and rheumatoid arthritis. The role of the IL-6/IL-6 receptor pathway in the documented acceleration of atherosclerosis in rheumatoid arthritis has not been examined. In a non-randomized prospective pilot study we asked whether endothelial dysfunction, defined as impaired flow mediated dilatation (FMD), and aortic stiffness, assessed by pulse wave velocity (PWV) improve after 3 and 6 monthly therapeutic infusions of the anti-IL-6 receptor antibody tocilizumab for active rheumatoid arthritis. We found that FMD increased from 3.3±0.8 to 4.4±1.2 to 5.2±1.9% (p=0.003), whereas PWV decreased from 8.2±1.2 to 7.7±1.3 to 7.0±1.0m/s (p