Alzheimer's disease is the most common form of dementia, which describes the loss of mental abilities, such as memory and reasoning.

Alzheimer's disease is a progressive condition, meaning it will continue to get worse as it develops. Unfortunately, there is no cure for the condition, although there is treatment that can slow down the development.

Early stages of the condition may begin with minor memory problems and difficulty saying the right words. These symptoms can then lead to frustration and mood swings.

Symptoms change as the condition develops, and it may lead to confusion, personality changes and a total change in behaviour.

What causes the symptoms of Alzheimer's disease?

Alzheimer's disease attacks nerves, brain cells and neurotransmitters (chemicals that carry messages to and from the brain).

The destruction of these parts causes clumps of protein to form around the brain's cells. These clumps are known as 'plaques' and 'bundles'. The plaques and bundles then start to destroy more connections between the brain cells, which makes the condition worse.

How common is Alzheimer's disease?

Age plays a large part in the development of Alzheimer's disease, although it is not the only cause.

It is most common in people over the age of 65, affecting around one person in 20. The risk increases with age, and people over 80 years old are thought to have a one in five chance of developing the condition.

It is rare for the condition to affect people below the age of 65, although it does occur in around one in every 1,000 people aged 65 or under.

It is estimated that around 450,000 people in the UK have Alzheimer's disease.

If you have Alzheimer's disease, it may have implications for driving. See the 'useful links' section for how to inform the DVLA about medical conditons.