Relationship Between Carotid Intima–Media Thickness, Serum Endocan and Hyaluronic Acid Levels in Multiple Sclerosis

<b>Background:</b> Multiple sclerosis (MS) is an immune-mediated neuroinflammatory disorder with a multifactorial etiology involving genetic susceptibility, environmental triggers, and vascular contributions. Carotid intima-media thickness (CIMT) is a significant marker of endothelial dysfunction. Endothelial cell-specific molecule-1 (endocan) and hyaluronic acid, key components implicated in endothelial and vascular remodeling, may significantly contribute to the inflammatory and vascular pathologies observed in MS. We aimed to investigate the relationship between CIMT and endothelial biomarkers, such as endocan and hyaluronic acid, in patients with MS. <b>Methods:</b> In this cross-sectional study, 100 patients with relapsing-remitting MS and 56 healthy controls were included. Demographic, clinical, laboratory, and imaging data were documented. CIMT was measured bilaterally using high-resolution B-mode ultrasonography. Serum endocan and hyaluronic acid levels were quantified via enzyme-linked immunosorbent assays. <b>Results:</b> MS patients exhibited significantly higher CIMT and serum endocan levels compared with controls (<i>p</i> < 0.001). CIMT values were significantly elevated in MS patients, with longer disease duration, higher expanded disability status scale scores, and an older diagnosis age (<i>p</i> < 0.05). However, serum endocan and hyaluronic acid levels did not significantly differ between MS subgroups based on disease duration, disability severity, and diagnosis age. Additionally, there was no correlation between CIMT and serum endocan and hyaluronic acid levels in MS patients (<i>p</i> > 0.05). <b>Conclusions:</b> Increased CIMT and serum endocan levels in MS patients may indicate endothelial dysfunction suggesting vascular involvement in MS. The lack of a correlation between CIMT and endocan and hyaluronic acid levels reveals the complexity of vascular and immune interactions in MS, which needs further research.