What is Multiple Sclerosis (MS)?

From the Guidelines

Multiple sclerosis (MS) is a chronic, inflammatory, and autoimmune disease of the central nervous system, leading to widespread focal degradation of the myelin sheath, variable axonal and neuronal injury, and disability in young adults. This condition is characterized by two main forms: relapsing-remitting MS (RRMS) and primary-progressive MS (PPMS) 1. The pathogenesis of MS is complex, involving genetic, immunological, and environmental factors, such as a common virus.

Key Characteristics of MS

• MS is a chronic and autoimmune disease
• It affects the central nervous system
• There are two main forms: RRMS and PPMS
• The cause of MS is unknown, but research suggests that genetic, immunological, and environmental factors are involved 1

Clinical Features of MS

• Weight loss, malnutrition, and cachexia are common features of patients with MS
• Reduced mobility and fatigue, inappropriate diet, physical difficulty for eating or drinking, poor appetite, poor sight, reduced cognition, and dysphagia are possible causes of weight loss and malnutrition in MS 1

Forms of MS

• Relapsing-remitting MS (RRMS): characterized by relapses and remissions, affecting about 85% of clinical cases
• Primary-progressive MS (PPMS): characterized by progressive neurological damages rather than relapses and remissions, affecting about 15% of clinical cases 1

From the Research

Definition and Characteristics of MS

• Multiple sclerosis (MS) is an autoimmune-mediated neurodegenerative disease of the central nervous system characterized by inflammatory demyelination with axonal transection 2
• MS affects an estimated 900 000 people in the US and typically presents in young adults (mean age of onset, 20-30 years) 2
• The prevalence of MS worldwide ranges from 5 to 300 per 100 000 people and increases at higher latitudes 2
• MS more commonly affects women (female to male sex distribution of nearly 3:1) 2

Symptoms and Diagnosis of MS

• MS typically presents with unilateral optic neuritis, partial myelitis, sensory disturbances, or brainstem syndromes such as internuclear ophthalmoplegia developing over several days 2
• Diagnosis is made based on a combination of signs and symptoms, radiographic findings (eg, magnetic resonance imaging [MRI] T2 lesions), and laboratory findings (eg, cerebrospinal fluid-specific oligoclonal bands), which are components of the 2017 McDonald Criteria 2

Treatment and Management of MS

• Nine classes of disease-modifying therapies (DMTs) are available for relapsing-remitting MS and secondary progressive MS with activity 2
• These drugs include interferons, glatiramer acetate, teriflunomide, sphingosine 1-phosphate receptor modulators, fumarates, cladribine, and 3 types of monoclonal antibodies 2
• One additional DMT, ocrelizumab, is approved for primary progressive MS 2
• Treatment with DMT can reduce the annual relapse rate by 29% to 68% compared with placebo or active comparator 2
• Switching from injectable immunomodulators to fingolimod is associated with fewer relapses, more favorable disability outcomes, and greater treatment persistence compared with switching to another injectable preparation following on-treatment activity of MS 3