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MS the Disease


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What is multiple sclerosis?

Multiple sclerosis is an unpredictable, often disabling disease of the central nervous system. Symptoms range from numbness and tingling to blindness and paralysis. The progress, severity, and specific symptoms of MS in any one person cannot yet be predicted, but advances in research and treatment are moving us closer to a world free of MS.

Who gets MS?

Most people living with MS are diagnosed between the ages of 20 and 50, with more than twice as many women as men being diagnosed with the disease. There are an estimated 8-10,000 children under the age of 18 who also live with MS. Studies indicate that genetic factors could make certain individuals more susceptible to the disease, but there is no evidence that MS is directly inherited. It occurs more commonly among Caucasians, especially those of northern European ancestry, but people of African, Asian, and Hispanic backgrounds are not immune.

How many people have multiple sclerosis?

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.

What are the typical symptoms of MS?

The progress, severity, and specific symptoms of MS in any one person cannot yet be predicted. The disease varies greatly from person to person, and from time to time, in the same person. For instance, one person might experience abnormal fatigue, another might have severe vision problems, and another could develop attention and memory issues. Even severe symptoms could disappear completely and the person could regain lost functions. In the worst cases, however, people can have partial or complete paralysis.

What causes these symptoms?

In MS, symptoms result when inflammation and breakdown occur in myelin, the protective insulation surrounding the nerve fibers of the central nervous system (brain and spinal cord). The nerve fibers themselves are also damaged. Myelin is destroyed and replaced by scars of hardened "sclerotic" patches of tissue. Such lesions are called "plaques," and appear in "multiple" places within the central nervous system. This can be compared to a loss of insulating material around an electrical wire, which interferes with the transmission of signals.

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 some rare instances, there are cases of MS that progress rapidly from disease onset and can be fatal.

Does MS always cause paralysis?

No. The majority of people living 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.

Is MS contagious?

No. MS is neither contagious nor directly inherited, although studies indicate that genetic factors might make certain individuals more susceptible to the disease.

Can MS be cured?

Not yet. However, advances in treating and understanding MS are being achieved daily and the progress in research to find a cure is very encouraging. In addition, many therapeutic and technological advances are helping people manage symptoms and lead more productive lives. Several FDA-approved medications are now available and have been shown to impact the underlying course of MS.

What medications and treatments are available for MS?

 The National Multiple Sclerosis Society recommends that people living with MS begin treatment with one of the disease modifying drugs, Avonex®, Betaseron®, Copaxone®, or Rebif® as soon as you are diagnosed with a relapsing form (the most common kind) of MS. Those drugs help to lessen the frequency and severity of MS attacks, reduce the accumulation of lesions in the brain, and slow progression of disability.

Novantrone® (mitoxantrone) is approved for reducing disability and/or frequency of relapses in patients with worsening relapsing MS. This is the first therapy approved in the United States for individuals with secondary progressive MS or who are experiencing a rapid worsening of the disease. In addition, approved by the FDA for return to market, is Tysabri®, which is generally recommended for patients who have had inadequate response to, or are unable to tolerate, other approved disease-modifying MS therapies for relapsing forms of MS.

Many therapies are available to treat symptoms such as spasticity, pain, bladder problems, fatigue, and weakness. People should consult with a knowledgeable physician to develop the most comprehensive approach to managing their MS.

Why is MS so difficult to diagnose?

In early MS, elusive symptoms that come and go might indicate any number of possible disorders. Some people have symptoms that are very difficult for physicians to interpret, and these people must "wait and see." 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.

What are the different types of MS?

In an effort to develop a common language when discussing, evaluating, and treating MS, the Society conducted an international survey among scientists who specialize in MS research and patient care. Analysis of the responses resulted in the publication of four disease courses in 1996. In 2013, the International Advisory Committee on Clinical Trials of MS updated the disease course definitions based on advances in the understanding of the disease process in MS and in MRI technology:
  • Clinically Isolated Syndrome (CIS): a first episode of neurologic symptoms caused by inflammation and demyelination in the central nervous system that may or may not go on to become MS.
  • Relapsing-Remitting MS (RRMS): a disease course characterized by clearly defined flare-ups (relapses) or episodes of acute worsening of neurologic function followed by remissions (with partial or complete recovery) during which no disease progression occurs. Frequency: Approximately 85% of people are diagnosed with RRMS.
  • Primary-Progressive MS (PPMS): a disease course characterized by nearly continuous worsening from the onset of symptoms, with or without occasional relapses. The rate or progression varies over time, with occasional plateaus. Frequency: Approximately 15% of people are diagnosed with PPMS.
  • Secondary-Progressive MS (SPMS): a disease course that follows after an initial RRMS course. Following an initial period of time with RRMS, the disease becomes more steadily progressive, with or without occasional relapses. 
    Frequency: If left untreated, 50% of people with relapsing-remitting MS develop this form of the disease within about 10 years of initial diagnosis.


© 2020 The National Multiple Sclerosis Society is a tax exempt 501(c)3 nonprofit organization. Its Identification Number (EIN) is 13-5661935.