Multiple Sclerosis

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What is multiple sclerosis?

Multiple sclerosis (MS) is a disease which causes demyelination of the brain and spinal cord nerve cells. When this occurs, axons (the parts of the nerve cells which conduct impulses to other cells), don't work as well. Myelin acts like insulation on electrical wires. As more areas or nerves are affected by this loss of myelin, patients develop symptoms because the impulses are diminished or lost. The specific symptom that someone experiences is related to the area of injury. In some cases, the axon of the nerve may be affected as well. As demyelination takes place, areas of inflammation and subsequent injury can be identified; these areas of injury are called lesions or plaques and are readily apparent on magnetic resonance imaging (MRI) studies.

What causes multiple sclerosis?

While multiple sclerosis is considered an autoimmune disorder, the exact cause hasn't yet been found. There are many theories regarding the reason that people develop multiple sclerosis; these theories range from vitamin D deficiency to a viral infection. Even consuming too much salt is being looked at as possible cause of multiple sclerosis. However, these theories have not been proven. Multiple sclerosis is not a contagious condition and cannot be passed from person to person.

What are the risk factors for developing multiple sclerosis?

Multiples sclerosis occurs predominantly in younger persons, with those aged 15 to 45 most likely to be diagnosed. The average age of diagnosis is about 30 years; however, multiple sclerosis has been identified at all ages. While multiple sclerosis can occur in children, this is very rare.

About 2.5 million people worldwide have been diagnosed with multiple sclerosis; of those, about 400,000 live in the United States. Women are about twice as likely as men to develop multiple sclerosis.

Genetic factors don't seem to play a large role in multiple sclerosis. Although people who have a first-degree relative with multiple sclerosis have a slightly higher risk of developing multiple sclerosis themselves, this risk is felt to be modest.

People who live in northern latitudes (especially Northern European countries) were previously identified as having a higher incidence of multiple sclerosis. However, over the past 30 years, this has begun to change and more cases of multiple sclerosis are now diagnosed in more temperate regions such as Latin America. It has further been identified that living in an area until approximately age 15 seems to give someone the relative risk of developing multiple sclerosis for that area. Persons younger than 15 who move assume the risk of the new location.

Lifestyle factors -- diet, exercise, tobacco use -- do not play a role in the risk of developing multiple sclerosis, unlike conditions such as stroke, heart disease, or diabetes, where these factors are very important.

Medically Reviewed by a Doctor on 12/11/2013

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Multiple Sclerosis MS picture

Multiple Sclerosis (MS) Treatment

How Is Multiple Sclerosis Treated?

There are many issues for the patient and physician to consider in treating multiple sclerosis. Goals may include:

  • improving the speed of recovery from attacks (treatment with steroid drugs);
  • reducing the number of attacks or the number of MRI lesions; or
  • attempting to slow progression of the disease (treatment with disease modifying drugs or DMDs).

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