Multiple sclerosis (MS) is a chronic immune-mediated demyelinating disease of the central nervous system characterized by inflammation, reactive gliosis, and progressive neuroaxonal damage resulting in heterogeneous clinical and histopathological manifestations. As MS often leads to disability at a young age, it represents a substantial socio-economic burden in developed countries. The etiopathogenesis of MS is multifactorial and incompletely understood, involving genetic, immunologic, and environmental factors. Recent research highlights immune responses to Epstein-Barr virus, blood-brain barrier disruption, microbiome-gut-brain axis alterations, oxidative damage, and mitochondrial dysfunction. Studying patients with newly diagnosed MS without significant comorbidities provides insight into early disease mechanisms before disability development or long-term treatment effects. This mini-review focuses on early vascular and metabolic alterations that may contribute to MS, including lipoprotein subfractions as markers of incipient atherosclerosis, endothelial dysfunction as an initiating vascular event, and autonomic nervous system imbalance during disease progression. It also addresses insulin sensitivity as a key metabolic factor alongside chronic inflammation and oxidative damage as interconnected mechanisms driving tissue injury. Metabolic changes reflecting neuronal impairment, mitochondrial dysfunction, and astroglial activation are detectable in both lesional and normal-appearing white matter in early stages. Reduced antioxidant capacity supports a role of oxidative damage in MS pathogenesis. Accelerated vascular aging, independent of traditional cardiovascular risk factors, may progress from endothelial dysfunction to structural atherosclerotic changes. Subtle alterations in lipoprotein profiles further suggest an increased risk of atherosclerosis, potentially influenced by inflammatory activity and oxidative damage, with possible sex-specific differences. Autonomic dysfunction appears to develop secondary to disease progression rather than as a primary driver of pathogenesis.
