Fact Sheet

What is Multiple Sclerosis?

Multiple Sclerosis (MS) is a chronic condition that affects the central nervous system. This system includes the brain and spinal cord. It contains the nerves that control everything your body does, such as thinking, feeling, seeing, smelling, tasting, and moving.

People without MS have nerves that are covered by an intact protective layer known as the myelin sheath. This covering helps to speed electrical signals in the brain. With MS, researchers think that the myelin sheath somehow becomes inflamed and damaged in small patches. It is not known what chain of events starts this damage, but once the injury occurs, electrical signals in the brain are slowed down.

MS is an autoimmune disease (a condition in which an individual’s immune system starts reacting against his or her own tissues) and cannot be spread from person to person. For unknown reasons, the immune system sees the myelin sheath as foreign and attacks it.

There are four types of MS:

• Clinically Isolated Syndrome or CIS is the earliest form of MS. CIS refers to a single episode of neurological symptoms suggestive of Multiple Sclerosis. Often, on investigation using MRI the doctor finds evidence of another abnormality in the brain or spinal cord. Having multiple attacks of symptoms defines relapsing-remitting MS, the most common disease course at the time of diagnosis.
• Relapsing-remitting MS (RRMS) is characterized by unpredictable but clearly defined relapses (also known as attacks, exacerbations or flare-ups) during which new symptoms appear or existing ones get worse. In the period between relapses, recovery is complete or nearly complete) to pre-relapse function (remission).
• Secondary-progressive MS (SPMS) follows a diagnosis of RRMS, Over time, distinct relapses and remissions become less apparent and the disease begins to progress steadily sometimes with plateaus. About half of the people with relapsing-remitting MS start to worsen within 10-20 years of diagnosis, often with increasing levels of disability.
• Primary-progressive MS (PPMS) is characterized by a slow accumulation of disability, without defined relapses. It may stabilize for periods of time, and even offer minor temporary improvement but overall, there are no periods of remission. Approximately 10 percent of people diagnosed with MS have PPMS.
• Progressive-relapsing MS (PRMS) is the rarest course of MS, occurring in only about 5 percent of people diagnosed. People with this form of MS experience relapses with or without recovery and steadily worsening disease from the beginning.

How is it manifested?

Symptoms of Multiple Sclerosis are unpredictable and vary greatly from person to person, and can fluctuate within the same person.

• optic neuritis, inflammation of the optic nerve, presents as sudden onset of visual blurring or loss of vision in one eye, particularly in the ventral visual field
• eye movement may bring on pain, light flashes or other visual symptoms
• management optic neuritis is the initial symptom for 16 per cent of people with MS and is a common occurrence during the course of the disease.
• onset to peak presentation usually happens within 4 days, and most recovery is usually achieved by about 5 weeks, although some improvement may continue up to a year. The pain usually resolves more quickly than the visual acuity.

Who is affected?

MS affects about one in 1,000 people and usually appears between the ages of 20 and 40, although it may occur at any age. Canada has the highest rate of Multiple Sclerosis in the world, with an estimated 100,000 Canadians living with the disease. While it is most often diagnosed in young adults aged 15-40, younger children and older adults are also diagnosed.

Diagnosis:

Neurological tests examine reflexes, eye movements, strength, sensation, and co-ordination. Your medical and family histories will also play an important role in the diagnosis.

Further tests might include:

• Magnetic resonance imaging (MRI), a type of scan that takes pictures of your brain and spinal cord
• Evoked potential, which measures nerve signals from your body to your brain. In MS, these signals are slower and weaker
• Spinal fluid examination, which checks the spinal fluid for signs of MS

To confirm a diagnosis of MS, a person must have signs of disease in different parts of the nervous system and at least two separate flare-ups. However, if a person has suffered only a single attack of symptoms that could be MS, an MRI may be done to evaluate the chance of this progressing to MS. Early treatment of a single flare-up may prevent or delay further relapses.

Additional Resources:

MS Society of Canada – www.mssociety.ca
National Office
Phone: 416-922-6065

The Multiple Sclerosis Society is the source of accurate, up-to-date information about MS, the most common neurological disease affecting young adults in Canada. Select the news releases and other information at the left to obtain the most recent information about exciting research developments and MS Society activities.

Books and Literature:

Multiple Sclerosis: The Guide to Treatment and Management (ISBN-13: 978-1932603514)
Author: Chris H. Polman
Special features include expert opinion statements for each MS therapy; a unique guide to the wide diversity of therapeutic options available; a thorough discussion of the usefulness, effectiveness, and side effects of individual treatments; a new chapter on unconventional therapies; and a detailed guide to further reading.

Multiple Sclerosis: The Facts You Need (ISBN-13: 978-1554700066)
Author: Dr. Paul O’Connor
This fourth edition of Multiple Sclerosis: The Facts You Need is a comprehensive guide to living with MS, supported by diagrams, case histories, a drug table, and an extensive list of helpful books and organizations. Topics include: • What MS is, and who gets it • How MS is diagnosed • Why the disease affects different people in different ways • How “relapsing-remitting” MS differs from “progressive MS” • How people with MS, and their families, can adapt their homes, careers, and lifestyles to cope with the disease • Which treatments work, which don’t, and what help is on the horizon.

The content contained in this document is for general information purposes. It is not intended to diagnose or treat a child.