Multiple Sclerosis is a disease of the brain and spinal cord (central nervous system). It interferes with the brain’s ability to control such functions as seeing, walking and talking, etc. MS is referred to as “multiple” because many scattered areas of the brain and spinal cord are affected. Multiple Sclerosis is called “sclerosis” because the disease involves “sclerosed” or hardened tissue in damaged areas of the brain and spinal cord.

Multiple Sclerosis is the most common central nervous system disease among young adults in Canada. Thousands of Canadians have MS and closely related disorders.

How Does Multiple Sclerosis Work?

The central nervous system acts like a switchboard, sending electrical messages along the nerves to various parts of the body. These messages control all of our conscious and unconscious movements. Most healthy nerve fibres are insulated by myelin, a fatty substance which aids the flow of messages. In MS, the myelin breaks down and is replaced by sclera (scar tissue). This distorts or even blocks the flow of messages. Body functions become uncontrolled because messages don’t get through correctly, and/or messages go to the wrong area.

What Causes Multiple Sclerosis?

The cause of MS is unknown and no cure has yet been discovered. Currently, there is no way to know who might get Multiple Sclerosis.
Scientists Have Four Theories as to the Cause of MS:

  • Virus Attack: When viruses enter the body, they multiply rapidly inside “body” cells. Most viruses cause symptoms quickly. Certain slow-acting viruses also reappear later, causing new symptoms. MS might be caused by some slow-acting viruses, or might be a delayed reaction to a common virus.
  • Immune Reaction: Our bodies have a built-in defense system which destroys “invaders” like viruses and bacteria. This defense system can “backfire” and start attacking the body’s own cells. This is called an Auto-immune reaction in which the body attacks its own tissues by mistake.
  • Genetic Predisposition: There is evidence that certain people may be at risk in developing MS because of their genetic make-up, however MS is not something you inherit. MS susceptibility is much more complex.
  • Combination: MS may involve both viruses and immune reaction in a susceptible person. When viruses invade the body, they take over body cells. The body’s defense system might become confused because some viruses take over parts of the cells… and it might attack both host cells and virus.

Who Gets Multiple Sclerosis?

Since there is still much unknown about MS, who gets it cannot be predicted. There is, however, a pattern as to who is more likely to develop Multiple Sclerosis.

  •  Young Adults: Symptoms usually appear between the ages of 20 and 40. MS seldom strikes people under 15 or over 50.
  •  Women: Slightly more women than men develop MS. MS isn’t connected with pregnancy. (Women with MS can have children.)
  •  People in the temperate zones: MS occurs more often between 40 and 60 degrees north and south latitudes. Closer to the equator, there are fewer cases of MS.
  • People with a predisposition: There seems to be a genetic predisposition to MS in certain population groups. How this works is not fully understood, since most people with MS do not have another family member with the disease.

Symptoms of MS Vary Greatly

The symptoms of MS can vary from person to person as well as from time to time in the same person. Symptoms may include:

  • Seeing double or uncontrolled eye movements
  • Speech problems such as slurring
  • Partial or complete paralysis of any part of the body
  • Extreme fatigue or an unusual tired feeling
  • Shaking of hands
  • Loss of coordination
  • Loss of bladder or bowel control
  • Numbness or prickly feelings
  • Staggering or loss of balance
  • Obvious dragging of feet

Early symptoms are usually slight and go away without treatment. As time goes on, however, they may become more frequent and more severe. A typical pattern is a short period of acute symptoms, followed by an easing or disappearance of symptoms for weeks, months or even years. Symptoms vary, depending on the part of the nervous system that is affected. For example, MS in the spinal cord might cause weakness, numbness and paralysis of the arms and legs.
Detecting MS can be difficult. It is often several years from the first symptoms to certain diagnosis because…

  • Early symptoms are often so slight that the person does not go to a docto;
  • Other diseases of the nervous system have some of the same warning signs as MS
  • No single lab test is yet available to definitely confirm or rule out possible MS

Doctors look for two basic signs before confirming MS:

  • Signs of nervous system damage Numbness and tingling of hands or feet, unexplained weakness or paralysis, might occur. (Two or more parts of the nervous system must be involved.)
  • Come and Go Pattern Symptoms of MS usually appear and disappear without warning, unlike those of other nervous system diseases.

Additional Facts About MS

  • People with MS can lead independent, active satisfying lives in spite of occasional disability.
  • Remissions are common. Many people with MS have few or no symptoms for months, even years.
  • A mild form of MS occurs in one out of three people with MS. They have few serious symptoms for many years after onset.
  • Three out of four people with MS are still active and can take care of daily needs many years after diagnosis of MS.

The life span for most people with MS is usually near normal.


There is currently no cure for multiple sclerosis, but much can be done to help people who have it remain independent, comfortable and productive.

  • Overall health maintenance: Proper rest and a balanced diet are very important.
  • Physical and occupational therapy: Exercise programs and muscle retraining may help recovery from MS attacks.
  • Psychotherapy and counseling: Individual and group therapy help people with MS and their families to cope with depression, anxieties and limitations.
  • Medication: Drugs are sometimes used to relieve specific symptoms. For example, muscle relaxers might relieve spasms. Some other drugs, such as steroids, sometimes seem to help to reduce the severity and duration of acute attacks.
  • On-going re-evaluation: The course of MS is unpredictable. Needs and disabilities change, so continuing medical supervision is essential. Not all medical problems are due to MS. A doctor can determine if symptoms are caused by another illness that requires treatment.
  • Training in the use of mobility and other adaptive aids may help people with MS to be more self-reliant.

Source: Multiple Sclerosis Society of Canada.