Similar to other chronic inflammatory conditions, spondyloarthritis is associated with increased cardiovascular risk, which is partly related to the impact of chronic inflammation on the vascular system. Suppression of vascular inflammation was suggested as a strategy to reduce cardiovascular risk in addition to intense control of traditional cardiovascular risk factors. The IL-23/IL-17 pathway plays a role in the pathogenesis of spondyloarthritis, however, its role in atherogenesis is controversial. Some studies suggest that IL-17A is pro-atherogenic, while others indicate that IL-17A is athero-protective.
Investigating the impact of medications on relatively rare events such as cardiovascular events, is challenging, as large cohorts and long follow-up are required. Therefore, surrogate measures that respond faster to interventions, such as changes in blood vessels that predict the development of these events, are often used instead.
18F-FDG PET/CT is a novel method to evaluate the extent of inflammation in the arteries. A study that included 18 patients with peripheral SpA initiating treatment with secukinumab, an IL-17A inhibitor, was presented. The objective of the study was to assess the effect of 3 months of treatment with secukinumab on arterial wall inflammation. Additionally, the relation between treatment response and change in vascular inflammation was evaluated. Arterial wall inflammation is measured in both the ascending aorta and carotids by 18F-FDG PET/CT.
The results of the study showed a significant improvement in disease activity as well as reduction in CRP levels. No change was observed in cholesterol levels. While no significant change was seen in vascular inflammation after 3 months in the entire group, a decrease in vascular inflammation was noted in patients who had good EULAR DAS response.
Although this is a relatively small study, it provides some insights on the impact of a new biologic agent on vascular comorbidities in SpA. The effect of IL-17 inhibition on cardiovascular diseases in SpA may depend on clinical response, which suggests that there is some overlap in the underlying mechanisms mediating SpA and atherosclerosis. Additional studies assessing the impact of other biologic and non-biologic DMARDs on comorbidities in SpA patients are needed.
Dr. Lihi Eder is an Assistant Professor of Medicine at the University of Toronto and Staff Rheumatologist and Director of the Psoriatic Arthritis Research Program at Women’s College Hospital. Dr. Eder is a Scientist at Women’s College Research Institute and associate member of the graduate faculty at the Institute of Medical Science.View Full Bio