- Multiple sclerosis (MS) is a chronic, progressive, and sometimes disabling, autoimmune
disease of the central nervous system.
- Multiple sclerosis affects 250,000 to 350,000 people in the United States;
about 2 million people are affected worldwide.
- Twice as many women have MS.
- A recent study (Neurology, 5/8/01) suggests that variants of a gene (ESR-1) may be linked to the two-fold risk of MS in women.
- About 200 new cases of MS are diagnosed in the U.S. every week.
- MS is the most common chronic disabling disease of the central nervous system in young adults.
- MS affects 1 in 1000 people in Western countries.
- Multiple sclerosis is an autoimmune disease, which means the body turns
against itself. When triggered by viruses or other agents, the immune system
mistakenly destroys its own healthy myelin tissue and cells rather than the
invading virus. Normally, myelin insulates nerves throughout the body, allowing
them to transmit impulses smoothly and quickly, without disruption. When myelin
is damaged in any way, plaques or scars form, which block the proper conduction
of electrical impulses to and from the brain. This produces the symptoms of
- In most patients, the disease begins at about 30 years of age with acute episodes of neurologic dysfunction followed by periods of partial or complete remission with clinical stability between relapses. This is called the "relapsing-remitting phase" of MS.
- Except in patients who continue to exhibit a relapsing-remitting pattern, this phase is usually followed by progressive clinical disability, with or without superimposed relapses and remissions.
- In a minority of patients, MS is progressive from the start.
- The symptoms and severity of MS vary greatly, depending on the areas of
the central nervous system that are affected. The most common problems involve:
- speech and swallowing
- bladder and bowel control
- cognitive function
- Specific kinds of symptoms that can occur include:
- Fatigue: a debilitating kind of general fatigue which is unpredictable
and out of proportion to the activity; fatigue is one of the most common
(and one of the most troubling) symptoms of MS.
- Visual disturbances: blurring of vision, double vision (diplopia), optic
neuritis, involuntary rapid eye movement, (rarely) total loss of sight.
- Balance and coordination problems: loss of balance, tremor, unstable
walking (ataxia), dizziness (vertigo), clumsiness of a limb, lack of coordination.
- Weakness: usually in the legs.
- Spasticity: altered muscle tone can produce spasms or muscle stiffness,
which can affect mobility and walking.
- Altered sensation: tingling, numbness (paresthesia), or burning feeling
in an area of the body, other indefinable sensations.
- Abnormal speech: slowing of speech, slurring of words, changes in rhythm
- Difficulty in swallowing (dysphagia).
- Bladder and bowel problems: the need to pass urine frequently and/or
urgently, incomplete emptying or emptying at inappropriate times, constipation,
loss of bowel control.
- Sexuality and intimacy: impotence, diminished arousal, loss of sensation.
- Cognitive and emotional disturbances: problems with short-term memory,
concentration, judgment or reasoning.
- Pain: facial pain, (such as trigeminal neuralgia), and muscle pains.
- Sensitivity to heat: this often causes a transient worsening of symptoms.
- Two medicines are available as disease modifying treatments: interferon beta and glatiramer acetate. These medicines reduce the frequency of relapses by about 30% although they are less effective in slowing the progression of disability.
- There are symptoms of MS common to many people. Most people with MS will
experience more than one symptom but no one will have all of them. There is
no "typical case" of MS. They are all different.
- MS is more common among Caucasians than other races. Some populations,
such as Eskimos and Bantus, rarely, if ever, are diagnosed with the disease.
The incidence of MS among Asian populations is very low.
- Research has shown that MS occurs more frequently in higher latitudes --
the closer to the equator or the more tropical a climate, the less likely
you are to develop MS.
- MS is five times more prevalent in the northern United States, Canada and
northern Europe than in other parts of the world. It is unknown whether this
is due to genetic or environmental factors.
- The cause of MS is still unknown. It may be caused by a virus, although
it is unlikely that there is just one MS virus.
- MS is not contagious.
- MS not an inherited disease, although there is some genetic susceptibility.
There is a higher risk for MS in families where it has already occurred. The
average person in the US has about one chance in 1,000 of developing MS. Children
or siblings of a person with MS have 1 chance in 100 of developing MS. The
identical twin of a person with MS has a 33 percent chance of developing MS.
Created: 3/24/2001  - Donnica Moore, M.D.
Reviewed: 5/22/2001  - Donnica Moore, M.D.