Introduction : Multiple sclerosis is a multifactorial disease, with many factors still unknown to this day. Studies on migrants play a significant role in the epidemiological and etiological research of this condition. Objective: This paper aims to study the impact of migration on the risk of developing multiple sclerosis. Methodology : A narrative review of the literature based on 80 articles retrieved from PubMed, Web of Science, Google Scholar, and ScienceDirect databases, using the following keywords: “multiple sclerosis”, “migration”, “migrants,” and “immigrants”, published from 1962 to 2022. Results : This review suggests that migration is a risk factor for multiple sclerosis. It supports the existence of an “age at migration” effect and highlights the particular role of environmental factors. The trend also points to an increased risk for second-generation immigrants compared to initial studies. Conclusion : Concepts regarding migrants and the risk of developing multiple sclerosis have evolved significantly over the past three decades. The older theory that those migrating after age 15 retain the risk of their country of birth is now less widely accepted, especially in cases of migration to high-prevalence regions, as they may influence future disease risk even into adulthood.
KeywordsMultiple SclerosisMigrationMigrants
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