What is dementia?

Dementia is an umbrella term used to describe a range of progressive neurological disorders, that is, conditions affecting the brain. There are over 200 subtypes of dementia, but the five most common are: Alzheimer’s disease, vascular dementia, dementia with Lewy bodies, frontotemporal dementia and mixed dementia. Some people may have a combination of different types of dementia and these are commonly called mixed dementia.

What causes dementia?

The brain is made up of nerve cells (neurones) that communicate with each other by sending messages. Dementia damages the nerve cells in the brain so messages can’t be sent from and to the brain effectively, which prevents the body from functioning normally.

Regardless of which type of dementia is diagnosed and what part of the brain is affected, each person will experience dementia in their own unique way.

Dementia in the UK

Dementia is a global concern but it is most often seen in wealthier countries, where people are likely to live into very old age. The Alzheimer’s Society (2014) reports there are over 850,000 people living with dementia in the UK today. Of these, approximately, 42,000 are people with young onset dementia, which affects people under the age of 65. As a person’s age increases, so does the risk of them developing dementia. It is estimated that the number of people living with dementia in the UK by 2021 will rise to over one million. Rates of diagnosis are improving but many people with dementia are thought to still be undiagnosed.

More about dementia

Read our ‘What is dementia’ leaflet for further information

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Types and symptoms of dementia

Find out more about the different types of dementia and the symptoms

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Getting a diagnosis

If you are concerned about your own memory, or you are worried about changes you have noticed with memory, communication, personality or behaviour of someone close to you, it is important to consult a GP as soon as possible, so that an accurate diagnosis is made

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