Introduction
Multiple sclerosis (MS) is the most common, chronic neuroinflammatory, demyelinating and neurodegenerative disease of CNS affecting individuals in their early adult life Prevalence estimates of cognitive impairment in MS have markedly increased, 40–70% of people with MS experience neuropsychological dysfunction in one or more cognitive domains at every stage of the disease. UP to 42- 65 % of MS patients are believed to have sleep disorders. Sleep abnormalities have a deleterious impact on cognitive functions in MS patients. It is critical to assess the cognitive and sleep affection as well as the bidirectional relationship in patients with multiple sclerosis thus improve overall health and quality of life.

Aim of the work: To assess the effect of different clinical variables of RRMS on cognition and sleep, as well as the relation between sleep disturbance and cognitive dysfunction in RRMS patients presented to Alexandria university hospitals.
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Subjects:The study was carried out on 50 subjects of confirmed Remitting relapsing MS patients with excluding Primary progressive and secondary progressive patients and patients with other associated autoimmune diseases, attending at Alexandria university hospitals.