Cause of aphasia

Aphasia is usually due to stroke or traumatic injury to the brain.

Aphasia and stroke can appear suddenly, but warning signs can occur:


  • Sudden weakness or numbness on one side of the body
  • Sudden trouble seeing
  • Sudden dizziness or trouble walking
  • Sudden headache for no reason
  • Sudden confusion or trouble talking and understanding

Communication problems

The ability to communicate using language is affected. Language includes:

  • Speaking
  • Understanding the speech of others
  • Reading
  • Writing
  • Gesturing
  • Using numbers
  • Aphasia affects everyone differently.
  • Intelligence is not affected by aphasia.

Recovering with aphasia

  • There is no medical “cure” for aphasia.
  • Problems communicating can last a long time.
  • Most people improve over time, particularly if speech therapy is provided.
  • People’s aphasia can be helped even 10 or more years after onset if they have access to appropriate intensive treatment.
  • New imaging studies show with time the brain can make new networks and heal.

Incidence of aphasia

  • More people have aphasia than have many other common conditions, including cerebral palsy, multiple sclerosis, Parkinson’s disease, or muscular dystrophy.
  • Stroke is a leading cause of long-term disability.
  • Stroke is the 3rd leading cause of death in the USA and Great Britain, after heart disease and cancer.
  • About 5,000,000 people survived strokes in the USA.
  • About 750,000 strokes occur each year in the USA.
  • About 1 third (225,000) of strokes result in aphasia.
  • There are at least 2,000,000 people in the USA with aphasia.
  • There are at least 250,000 people in Great Britain with aphasia.

Aphasia statistics

Pulled from our 2016 national survey on aphasia awareness.

  • 84.5% of people have never heard the term “Aphasia.”
  • 8.8% of people have heard of aphasia and can identify it as a language disorder.
  • 34.7% of people that are “aphasia aware” either have aphasia or know someone that does.
  • 31% of people agree or give a neutral response to the statement: “If a person has difficulties with speech, they also have intellectual deficiencies.”
  • 84.1% of people make a connection between stroke and brain injury and difficulties with communication.
  • 15.3% of people recall first hearing about aphasia from newspapers, magazines or online publications.

Additional facts


Research study demonstrating impact of aphasia on the quality of life for people

Aphasia Has Greater Negative Impact on a Person’s Quality of Life than Cancer or Alzheimer’s Disease.

  • Researchers studied health-related factors affecting quality of life for hospital residents in Ontario, Canada.
  • They examined the impact of 60 different diseases and 15 conditions on quality of life of 66,193 people.
  • Results showed aphasia has the largest negative impact on quality of life, more than cancer and Alzheimer’s disease.
  • The negative effects of aphasia on an individual’s quality of life includes their inability to communicate with and engage their family, friends, doctors and their wider community.
  • Health care providers should act so as to significantly improved services for people with aphasia as people with aphasia frequently cannot express their wants and needs unassisted.
  • The next stage is to ensure that those who have the power to influence the provision of services from health and social systems are fully aware of the impact that aphasia has and the impact that services for aphasic people and their relatives can have when readily provided.



Lam, J.M.C. & Wodchis, W. P. (2010) The relationship of 60 disease diagnoses and 15 conditions to preference-based health-related quality of life in Ontario hospital-based long-term care residents. Medical Care, 48, 380-387.