Multiple sclerosis is a disease that attacks the nervous system. The nervous system consists of the brain, spinal cord and nerves. The disease specifically attacks the myelin sheath, which is the protective covering of the nerves. Myelin is necessary for the transmission of electrical signals. As the disease progresses and damage to myelin worsens, the flow of nerve impulses is interrupted. The result is a wide variety of symptoms that vary based on the area affected.
There are four types of multiple sclerosis:
- Clinically Isolated Syndrome
This type is characterized by the first episode of neurologic symptoms suggestive of the disease.
- Relapsing-remitting multiple sclerosis
The most common disease course at the time of diagnosis. It is characterized by flare-ups or exacerbations (relapses) followed by periods of recovery (remission). Relapses are episodes during which new symptoms appear or existing ones worsen. In the period between relapses, the patient can recover partially or completely. There is little disease progression between relapses.
- Primary-progressive multiple sclerosis
Patients with primary-progressive MS experience a gradual worsening of their symptoms. This type is said to be "active" when an acute relapse occurs or "with progression" when symptoms appear discretely but do not disappear.
- Secondary-progressive multiple sclerosis
This type of MS follows a diagnosis of relapsing-remitting MS and is characterized by a steady progression of the disease. Over time, distinct relapses and remissions become less apparent.
The disease is most often diagnosed in individuals between the ages of 15 and 40 years and affects twice as many women. The course of MS varies from person to person and certain individuals eventually require the use of a cane or a wheelchair, if only temporarily (during the remission period following a relapse). It is important to note that the life expectancy of those with multiple sclerosis is not significantly reduced when compared to that of a healthy person.
Experts have yet to determine what causes multiple sclerosis. Several theories have been put forth, with the most plausible one being that multiple sclerosis is an autoimmune disease. This means that at some point, the body's defense system (immune system) ceases to recognize the myelin that covers the nerves as being part of the individual's body. To defend itself, the body attacks the myelin, damaging it in the process and preventing it from properly carrying out its functions.
The course of multiple sclerosis is unpredictable and its symptoms vary from person to person and even from one day to another. Symptoms are based on the nerves affected. Heat aggravates symptoms in many with MS. Hot showers, spas and travel to tropical destinations can worsen symptoms. Here are examples of some of the most common symptoms:
- numbness or tingling
- heat intolerance
- loss of vision
- impaired balance
- coordination problems
- bladder dysfunction (incontinence)
- cognitive impairment (concentration, memory)
- sexual dysfunction
Multiple sclerosis is diagnosed by a doctor or, more specifically, a neurologist (specialized in the treatment of the nervous system). Although interviewing the patient and establishing a list of symptoms may help in the diagnosis, additional tests are required to evaluate the condition of the nerves.
Magnetic resonance imaging (MRI) is commonly used to look for visible lesions. The neurologist can also ask for a lumbar puncture, which involves taking a small amount of fluid from the base of the spine. And lastly, brain responses can be examined using evoked potential, a test that assesses nerve impulses.
While there is no cure for multiple sclerosis, certain medications have proven helpful in reducing the frequency of relapses and slowing disease progression. Some are administered orally, while other are injected subcutaneously or intravenously.
Other treatments are aimed at directly relieving symptoms such as fatigue, cramps or muscle spasms, pain, mood and constipation.
Health Canada has authorized access to medical marijuana to help relieve pain and muscle spasms associated with multiple sclerosis.
Knowledge is power
It is in your best interest to gather as much information as possible and to ask for all the support you need in order to maintain the best possible quality of life.
For more information or for support :
Multiple Sclerosis Society of Canada