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Multiple sclerosis

doi: 10.1097/01.NNN.0000267386.41653.e4
Department: the Waiting Room: By the Numbers

Multiple sclerosis is a chronic and unpredictable neurological disease. It is thought to be an autoimmune disorder, which causes the immune system to attack healthy tissue. MS symptoms result when such an attack affects myelin, the protective insulation surrounding nerve fibers of the brain and spinal cord.


The approximate—and, according to some patient advocacy groups, vastly underestimated—number of Americans living with multiple sclerosis. The Centers for Disease Control and Prevention do not require U.S. physicians to report new cases, and because symptoms can be completely invisible, the numbers can only be estimated.


Percentage of people with relapsing-remitting MS, in which they experience episodes of attacks followed by partial or complete recovery periods.

1 in 750:

The average American's chance of developing MS.

1 in 3:

The chance of an identical twin of someone with MS developing the disease.

2 to 1:

The ratio of women to men with MS.


Percentage of those with MS who report feeling extreme fatigue, a common symptom and a major reason for unemployment among people with it.


Portion of people with MS who will not become paralyzed and will remain able to walk.

Source: National Multiple Sclerosis Society. Call 1-800-FIGHT-MS (1-800-344-4867) or go to for more information.

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