Epidemiology
 

ALS Prevalence: The Most Common
Adult-Onset Motor Neuron Disorder

ALS incidence and prevalence in Canada
In an estimated Canadian population of 34 million, approximately 2,000–3,000 people in Canada currently have ALS2
how often ALS is diagnosed
In any given year, about two new cases of ALS per 100,000 people will be diagnosed in Canada2
The relatively low prevalence is potentially understated due to the rapid progression of ALS.3

The Prevalence of ALS Increases by Age2,4

Age distribution of patients with ALS in Canada

prevalence of ALS by age chart
ALS prevalence chart

ALS risk factors among Canadian population1,2,5

  • Common age of onset is between 40–70 years of age
  • ALS is diagnosed in both men and women of all ethnic and socio-economic groups
  • Sporadic ALS occurs more in men than in women (1.6:1)
  • Other risk factors include family history (genetic and heredity factors) and smoking
  • Types of ALS1
  • Sporadic ALS is most common
  • Affects 90–95% of patients
  • Familial ALS is the hereditary form
  • Affects 5-10% of patients
Survival Rates
 

ALS Prognosis: ALS Is Incurable and Can Progress Rapidly

  • The majority of patients die within 2 to 5 years of diagnosis
  • 20% live longer than 5 years
  • 10% live longer than 10 years1
  • Rates of disease progression among ALS patients vary1
  • Patients who receive a diagnosis at an earlier age have a slightly better prognosis6
The variable rate of ALS progression makes disease prognosis difficult to determine.6
Clinical Challenges
 

ALS Continues to Pose Numerous Clinical Challenges1,6

Disease Rarity: ALS is a rare and rapidly progressive motor neuron disease, and, even in multicentre trials, patient enrolment can be slow. Recruitment remains an obstacle for all clinical trials.

Disease Heterogeneity: The rate of progression of ALS varies widely among patients. Some patients may not survive past a year while others may live for more than a decade.

Lack of Biomarkers: To date, there remains a lack of reliable biomarkers that are exclusive to ALS for predicting disease progression and prognosis.

Numerous Outcome Measures: A multitude of outcome measures are used to provide evidence of clinically meaningful change in ALS clinical trials, such as survival time and functional status. Each of these measures has its strengths and their own limitations.
REFERENCES: 1. ALS Society of Canada. A guide to ALS patient care for primary care physicians. Accessed August 2020 at: https://als.ca/wp-content/uploads/2017/02/A-Guide-to-ALS-Patient-Care-For-Primary-Care-Physicians-English.pdf 2. ALS Society of Canada. A manual for people living with ALS. Accessed August 2020 at: https://als.ca/wp-content/uploads/2017/02/2012-Manual-People-Living-With-ALS-English.pdf 3. Berry JD, Cudkowicz ME. New considerations in the design of clinical trials for amyotrophic lateral sclerosis. Clin Investig (Lond) 2011;1(10):1375-1389. 4. Canadian Institute for Health Information. The burden of neurological diseases, disorders and injuries in Canada. Accessed August 2020 at: https://secure.cihi.ca/free_products/BND_e.pdf 5. ALS Society of Canada. ALS guide. Accessed August 2020 at: https://www.als.ca/wp-content/uploads/2020/03/ALS-guide-ON-EN-WEB.pdf 6. Zarei S, Carr K, Reiley L, et al. A comprehensive review of amyotrophic lateral sclerosis. Surg Neurol Int 2015;6:171.