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Multiple Sclerosis FAQs

Discover more about Multiple Sclerosis.

Just the facts

Frequently asked questions about MS and the National MS Society.

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Bienvenidos a este su centro de información sobre la esclerosis múltiple (EM).


Disproved theories

Over the years, people have suggested many different causes for MS. Here are some of the most popular theories that have been proved incorrect. 

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What is multiple sclerosis?

Multiple sclerosis is a chronic, unpredictable disease of the central nervous system (CNS), which is made up of the brain, spinal cord and optic nerves. It is thought to be an immune-mediated disorder, in which the immune system incorrectly attacks healthy tissue in the CNS.

MS can cause many symptoms, including blurred vision, loss of balance, poor coordination, slurred speech, tremors, numbness, extreme fatigue, problems with memory and concentration, paralysis, and blindness and more. These problems may come and go or persist and worsen over time. Most people are diagnosed between the ages of 20 and 50, although individuals as young as 2 and as old as 75 have developed it.

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Who gets MS?

Anyone may develop MS but there are some patterns. More than two to three times as many women as men develop MS and this gender difference has been increasing over the past 50 years. Studies suggest that genetic risk factors increase the risk of developing MS, but there is no evidence that MS is directly inherited. Environmental factors, such as low Vitamin D and cigarette smoking have also been shown to increase the risk of MS. MS occurs in most ethnic groups, including African-Americans, Asians and Hispanics/Latinos, but is most common in Caucasians of northern European ancestry.
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How many people have MS?

More than 2.3 million people are affected by MS worldwide. Because the Centers for Disease Control and Prevention (CDC) does not require U.S. physicians to report new cases, and because symptoms can be completely invisible, the prevalence of MS in the U.S. can only be estimated. The Society continues to advocate for the establishment of a national registry that will track the number of people living with MS and has made a commitment to re-evaluate the current prevalence estimate and investigate the process by which an updated estimate can be identified.

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What are the different types of MS?

While there is no way to predict with any certainty how a person’s MS will progress, four basic disease courses have been defined:
  • Clinically isolated syndrome-first episode of neurologic symptoms caused by inflammation and demyelination in the central nervous system.
  • Relapsing-remitting MS -periods of relapses (also called attacks or exacerbations) that subside, with full or partial recovery, and no disease progression between attacks.
  • Secondary progressive MS-a relapsing-remitting course that later evolves into a more consistently progressive course, with or without relapses.
  • Primary progressive MS is characterized by a gradual but steady progression of disability from the onset of symptoms, with few or no relapses or remissions.
 Read more about the types of MS.
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What are the typical symptoms of MS?

Because MS causes damage in the CNS, nearly any function can be adversely affected. However, the most common symptoms are overwhelming fatigue, visual disturbances, altered sensation and difficulties with mobility.

Symptoms of MS are unpredictable, and vary in type and severity from one person to another and in the same person over time. Symptoms may disappear or remit completely or they may persist and may worsen over time.
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What causes the symptoms?

MS symptoms occur when the immune-system produces inflammation within the CNS.  The inflammatory attack damages myelin, (the protective insulation surrounding nerve fibers), oligodendrocytes (cells that make CNS myelin) and sometimes the underlying nerve fiber. The damage caused by inflammation can produce symptoms that resolve over weeks to months or symptoms that are permanent. 

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Does MS always cause paralysis?

No. Moreover, the majority of people with MS do not become severely disabled. Two-thirds of people who have MS remain able to walk, though many will need an aid, such as a cane or crutches, and some will use a scooter or wheelchair because of fatigue, weakness, balance problems, or to assist with conserving energy. 
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Is MS fatal?

Life expectancy for people with MS has increased over time. We believe this is due to treatment breakthroughs, improved healthcare and life style changes. Recent research however, indicates that people with MS may live an average of about seven years less than the general population because of disease complications or other medical conditions. Many of these complications are preventable or manageable. Attention to overall health and wellness can help reduce the risk of other medical conditions, such as heart disease and stroke, that can contribute to a shortened life expectancy. In rare instances, MS can progress rapidly from disease onset and can be fatal.

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Can MS be cured?

Not yet. There are now FDA-approved medications that have been shown to "modify" the course of MS by reducing the number of relapses and delaying progression of disability to some degree. In addition, many therapeutic and technological advances are helping people manage symptoms. Advances in treating and understanding MS are made every year, and progress in research to find a cure is very encouraging.

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What can be done about MS now?

The National Multiple Sclerosis Society recommends that a person consider treatment with one of the FDA-approved "disease-modifying" drugs as soon as possible following a definite diagnosis of MS with active or relapsing disease. These medications help to reduce the frequency and severity of MS attacks, the number of new lesions in the CNS and may slow the progression of disability. Some of these medications are also approved for people who have experienced an initial demyelinating episode (clinically isolated syndrome) and are at high risk of developing MS. Studies have shown them to be effective in delaying disease onset.

In addition to these medications that address the disease process, there are many medications and other strategies to manage MS symptoms. People should consult a knowledgeable MS care provider to develop a comprehensive plan to manage their MS.
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Why is early treatment important?

Early damage in the CNS can occur even before people are experiencing any symptoms. Studies show that the best chance for reducing long-term disability is during the early relapsing phase of the disease, which is characterized by inflammation. Given that the medications currently available all primarily target inflammation, early and ongoing treatment helps to minimize this inflammation and also reduces damage to nerve fibers (axons) and loss of brain tissue.
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Why is MS so difficult to diagnose?

Diagnosing MS can be a challenging process. In early MS, symptoms may be non-specific and suggestive of several disorders of the nervous system. Early symptoms that come and go may be ignored. While no single laboratory test is yet available to prove or rule out MS, magnetic resonance imaging (MRI) is a great help in reaching a definitive diagnosis.  Diagnostic criteria that incorporate MRI findings have been developed and revised by experts in the field and have helped providers make an accurate and timely diagnosis.


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