Multiple sclerosis (MS) is a chronic, often disabling disease that attacks the central nervous system (CNS), which is made up of the brain, spinal cord and optic nerves. The progress, severity, and specific symptoms of MS are unpredictable and vary from one person to another.
Multiple sclerosis usually affects women more than men. The disorder most commonly begins between ages 20 and 40, but can be seen at any age.
The exact cause is not known, but multiple sclerosis is believed to result from damage to the myelin sheath, the protective material which surrounds nerve cells. It is a progressive disease, meaning the nerve damage (neurodegeneration) gets worse over time.
In addition to nerve damage, another part of multiple sclerosis is inflammation. Inflammation occurs when the body's own immune cells attack the nervous system. The inflammation destroys the myelin, leaving multiple areas of scar tissue (sclerosis). It also causes nerve impulses to slow down or become blocked, leading to the symptoms of MS. Repeated episodes, or flare ups, of inflammation can occur along any area of the brain and spinal cord.
Because we do not know what causes multiple sclerosis, there is no solid information on how to prevent it.
Scientists believe that a combination of several factors may be involved. Studies in the areas of
immunology, epidemiology and genetics are conducted in an effort to answer this important question.
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