Multiple Sclerosis in Low- and Middle-Income Countries: Between Epidemiological Transition and Structural Constraint

Multiple sclerosis (MS) is increasingly recognized as a global disease, with rising prevalence beyond traditionally high-income regions. In low- and middle-income countries (LMICs), however, MS remains underdiagnosed and undertreated, reflecting limitations in healthcare infrastructure, access to diagnostics, and availability of disease-modifying therapies. This viewpoint argues that MS in LMICs should be understood as a condition shaped not only by biological mechanisms but also by systemic inequities that influence its detection, progression, and outcomes. Delayed diagnosis, limited access to imaging and specialist care, and fragmented health systems contribute to higher disability and poorer long-term prognosis. At the same time, epidemiological transitions and urbanization may be increasing disease incidence, placing additional strain on already constrained systems. We explore how these factors interact and propose context-sensitive strategies to improve care, including strengthening diagnostic pathways, prioritizing essential therapies, and developing integrated care models adapted to resource-limited environments. Addressing MS in LMICs requires aligning global advances in neuroimmunology with local feasibility to ensure equitable neurological care.