Multiple sclerosis: risk factors and therapies

Multiple Sclerosis (MS) is a potentially progressive chronic autoimmune neurodegenerative disorder of the central nervous system, resulting from an autoimmune attack on the white matter. The main agents responsible for the development of MS involve exogenous, environmental, and genetic factors. The activation of the immune system triggers an inflammatory cascade at the level of nerve fibers and myelin. Regarding genetic predisposition, it is important to note that MS is not a hereditary disease. Infectious agents have also been studied as potential causes of the onset of MS. Several studies have shown that the Epstein-Barr Virus (EBV), responsible for mononucleosis, can influence the pathogenesis of MS, just as an altered mycobiome can play a role in triggering the pathology. Among the environmental factors, the prevalence of the disease observed as one moves away from the Equator is of particular etiopathogenetic relevance. This finding may be correlated with sun exposure and vitamin D (VD) levels. The aim of this article is to explore the complex risk factors and etiopathogenesis of MS, focusing on the interplay between genetic predisposition, environmental influences (such as VD deficiency and viral infections, particularly EBV), and the gut microbiome in the development and progression of the disease. This review was based on a comprehensive search of available medical and scientific literature, including observational studies (cohort, case-control, cross-sectional), metaanalyses, and systematic reviews, specifically addressing individuals with a confirmed MS diagnosis and studies related to genetic, environmental, or immunological risk factors. Studies that did not meet methodological standards, lacked relevant data, or were published in languages not understood by the authors were excluded.