What is Alzheimer's disease?

Alzheimer's disease was first described by a German neurologist Alois Alzheimer. It is a disease of the brain, causing dementia which is progressive and irreversible impairment of brain function.


Alzheimer's disease is estimated to start 20-30 years before the onset of slow, insidious symptoms. As more of the brain is damaged, the symptoms become more severe.

This disease greatly impacts on the daily life of the patient: there is gradual intellectual deterioration, and disturbance in behaviour and mood, ultimately causing difficulty to cope and loss of autonomy.


Alzheimer's disease affects approximately 417,000 people in the UK, making it the most common cause of dementia.
  • Dementia affects 1 in 14 people who are over the age of 65 and this rises to 1 in 6 in the over 85 year-olds.
  • There are more than 16,000 people below the age of 65 with dementia.
  • These figures are likely to be underestimates due to under-diagnosis.
  • According to an American study, the number of patients with Alzheimer's Disease will increase by a factor of 4 in 2050: The number of patients in the world could go up from the current 24 million, to 42 million by 2020 and 81 million in 2040.

For more information on Alzheimer's DIsease, please visit the Alzheimer's Society website: