Multiple Sclerosis Society of Canada

What is MS?

Canada has the highest rate of multiple sclerosis (MS) in the world, with an estimated 100,000 Canadians living with the disease. While it is most often diagnosed in young adults aged 15 to 40, younger children and older adults are also diagnosed with the disease.

MS is currently classified as an autoimmune disease of the central nervous system (brain, spinal cord). The disease attacks myelin, the protective covering of the nerves, causing inflammation and often damaging the myelin. Myelin is necessary for the transmission of nerve impulses through nerve fibres. If damage to myelin is slight, nerve impulses travel with minor interruptions; however, if damage is substantial and if scar tissue replaces the myelin, nerve impulses may be completely disrupted, and the nerve fibres themselves can be damaged.

MS is unpredictable and can cause symptoms such as extreme fatigue, lack of coordination, weakness, tingling, impaired sensation, vision problems, bladder problems, cognitive impairment and mood changes. Its effects can be physical, emotional and financial. Currently there is no cure, but each day researchers are learning more about what causes MS and are zeroing in on ways to prevent it.

We are here to help. No one needs to face MS alone. In communities across Canada, the MS Society provides information, support, educational events and other resources for people living with MS and their families. Learn more about the programs and services we offer.

Researchers funded by the MS Society are working to find the cause of MS, develop better treatments with less side effects, and ultimately cure the disease for everyone who is affected by it. Learn more about the research we fund.

What causes MS?

Despite decades of research, the cause remains a mystery. The best current evidence suggests that lifestyle, environmental, genetic and biological factors all contribute. All these areas are being actively examined. Studies funded by the MS Society are asking if certain risk factors, such as gender, age, family history or lifestyle habits impact a person’s susceptibility to MS.

Who gets MS?

MS can occur at any age, but is usually diagnosed between the ages of 15 to 40, peak years for education, career- and family-building. MS has been diagnosed in children as young as two years old – and in far older adults. It has some peculiarities: MS is three times as likely to occur in women as in men and is more common in people of northern European background.

How is MS diagnosed?

MS often develops slowly, and the symptoms may not appear right away. Upon initial symptoms, a person’s family doctor will refer him or her to a neurologist, who will conduct a full medical history and a neurological examination to assess things like eye moment, strength and coordination. To reach a confirmed diagnosis of MS, the neurologist may employ additional tests, including a Magnetic Resonance Imaging (MRI) scan which looks for tissue damage in the brain.

The severity of MS, progression and specific symptoms cannot be predicted at the time of diagnosis.

Read more information for those newly diagnosed with MS.

Does everyone experience MS the same way?

No. Everyone’s experience with MS is different. In addition, MS is divided into several basic categories, depending on the pattern of the individual’s disease. The categories are:

  1. Relapsing Remitting MS (RRMS) – Characterized by unpredictable but clearly defined periods during which symptoms are apparent. These ‘’relapses” are also known as episodes, attacks, exacerbations, or flare-ups. Relapses can last for varying periods (from a few days to several months) and are followed by periods of recovery, or ‘remission’ during which many functions return. About 85% of people are diagnosed with this form of MS.
  2. Progressive MS (PMS) – A percentage of people with RRMS will eventually transition to a state in which relapses and remissions no longer occur. Symptoms may persist and disability slowly and continually increases. This is referred to as secondary progressive MS. Individuals who accumulate disability and experience worsening of symptoms right from the start are diagnosed with primary progressive MS.
  3. Progressive Relapsing MS – People with this form of MS experience steadily worsening disease from the beginning, but also experience relapses with or without recovery.

Learn more about the various types of MS.

Why do MS symptoms develop?

MS is thought to be an autoimmune disease, which means the immune system - designed to protect against intruders such as viruses and bacteria - attacks tissues in the body. In the case of MS, the tissue that is targeted is myelin. Without myelin the communication between nerve cells is disrupted, and the body does not receive the instructions necessary to perform basic functions like speaking, seeing, walking and learning. Myelin damage can also lead to deterioration of the exposed nerves, resulting in irreversible damage to them. As a chronic neurological disease, MS can also have a dramatic effect on energy levels, sleep and overall quality of life. Learn more about the symptoms of MS here.

Is MS fatal?

No. MS is not fatal for the vast majority of people living with the disease. Most people who have MS can expect a normal or near-normal lifespan, thanks to improvements in symptom management and the MS disease-modifying therapies.

Is there hope for a cure?

Absolutely. Researchers are zeroing in on what causes MS and exploring ways to repair the damage it causes and ways to prevent MS from occurring. The MS Society of Canada and its related MS Scientific Research Foundation fund investigation into many aspects of the disease including:

  1. Progression/therapies – Examines current or potential therapies for MS and seeks to improve imaging technology to better visualize what happens in the brain.
  2. Cause/risk factors – Investigates potential triggers of MS and why some factors may increase susceptibility to MS.
  3. Nerve damage/repair – Focuses on the cellular mechanisms that result in either damage or repair of myelin and underlying nerve cells.
  4. Symptom management/quality of life – Probes how MS affects day-to-day living and develops treatments that more effectively manage symptoms.

Learn more about the latest news in MS research.