About ALS

Amyotrophic lateral sclerosis (also known as ALS, Lou Gehrig’s disease, or motor neuron disease) is a disease that progressively paralyzes people because the brain is no longer able to communicate with the muscles of the body that we are typically able to move at will. Over time, as the muscles of the body break down, someone living with ALS will lose the ability to walk, talk, eat, swallow, and eventually breathe.

ALS is not contagious. There is no cure for ALS and few treatment options for the majority of people living with the disease. Approximately 80 per cent of people with ALS die within two to five years of being diagnosed.

How ALS works in the body

ALS Quick Facts

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Our brain is connected to our muscles through millions of specialized nerve cells, called motor neurons, which serve as our bodies’ internal wiring and enable us to move our bodies as we choose. Motor neurons work in pairs: an upper motor neuron in the brain extends to the brainstem at the back of the neck or the spinal cord, and a lower motor neuron extends from the brainstem or spinal cord to the muscle. The brain sends a signal along these motor neurons telling a muscle to contract.  This signal is an electrical impulse created by chemicals in our neurons.

In ALS, motor neurons gradually break down and die. This means that the brain can no longer communicate with the muscles of the body. As a result, the muscles become weak and eventually someone living with ALS will be unable to move them.

What are the types of ALS?

The most common form of ALS is called sporadic ALS, meaning the disease can affect anyone regardless of gender, ethnicity or age—although it most often affects people between the ages of 40 and 60.

The other type of ALS is called familial ALS, which means it is capable of being passed from a parent to his or her child. Approximately 5 to 10% of ALS cases are familial.

Regardless of whether someone has sporadic or familial ALS, 30% of all people with the disease have a form referred to as Bulbar ALS. In the early stages of Bulbar ALS, the motor neurons in the corticobulbar area of the brainstem are the first to be affected. This means that the muscles of the head, face and neck become paralyzed before muscles in other parts of the body. Learn more.

ALS is often confused with Multiple Sclerosis and Muscular Dystrophy. Learn about the differences.

What Causes ALS?

There is no one thing that causes ALS. Rather, ALS is recognized as having multiple interacting causes that are likely based on changes in people’s genes, and possibly contribution of environmental factors. A number of genes have been identified as playing a role in the development of ALS. Through research, we are learning more about ALS and the multiple factors that may trigger its development.

ALS Figures*

  • More than 200,000 people around the world are living with ALS.
  • An estimated 4,000 Canadians are currently living with ALS.
  • Each year approximately 1,000 Canadians die from ALS. A similar number of Canadians are diagnosed with ALS each year.
  • 80% of people with ALS die within 2-5 years of diagnosis.




Source links are current as of September 2018.