Multiple Sclerosis

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Multiple Sclerosis

Multiple sclerosis (MS) involves an immune-mediated process in which an abnormal response of the body’s immune system is directed against the central nervous system (CNS). The CNS is made up of the brain, spinal cord and optic nerves.

Within the CNS, the immune system causes inflammation that damages myelin; the fatty substance that surrounds and insulates the nerve fibers as well as the nerve fibers themselves, and the specialized cells that make myelin.

  • When myelin or nerve fibers are damaged or destroyed in MS, messages within the CNS are altered or stopped completely.

  • Damage to areas of the CNS may produce a variety of neurological symptoms that will vary among people with MS in type and severity.

  • The damaged areas develop scar tissue which gives the disease its name multiple areas of scarring or multiple sclerosis.

  • The cause of MS is not known, but it is believed to involve genetic susceptibility, abnormalities in the immune system and environmental factors that combine to trigger the disease.

  • People with MS typically experience one of four disease courses (types of MS). There are over a dozen treatments to help modify the MS disease process.
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Multiple sclerosis affects about 400,000 people in the United States, and about 2 1/2 million worldwide. In the United States, the prevalence of the condition that is, the number of people who have it compared with the general population is nearly 90 cases per 100,000 people.

The prevalence of MS varies with location and increases with distance from the equator. We don’t know whether this has to do with an environmental influence, a genetic influence, or something else.

MS usually shows up when a person is between 20 and 40 years of age, with 32 the mean age. It can occur in young children, however.

MS is more common is women than men, with recent studies suggesting a female to male ratio as high as three to four women with MS against one man.

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