Alzheimer's is the most common disease that causes dementia. The word dementia is used to describe a group of symptoms – often including memory loss, confusion or mood changes that are severe enough to affect day-to-day life.

What is young-onset Alzheimer's?

Although often thought of as a disease that affects older people, around 5% of people with Alzheimer’s disease are under 65. This is called young-onset or early-onset Alzheimer’s. Someone diagnosed with Alzheimer's disease before they are 65 is considered to have young-onset dementia. There are other types of young-onset dementia such as frontotemporal dementia and vascular dementia.

If you are worried about yourself or someone else who is showing symptoms of dementia, talk to your doctor. They will be able to rule out other health problems such as depression, tyroid disorders or vitamin deficiencies that may cause similar symptoms in younger people. They will also be able to refer you to a specialist for other tests if necessary.

Early-onset Alzheimer's

This leaflet aims to give an introduction to early-onset Alzheimer’s disease. It’s for anyone who might be worried about themselves or somebody else.


Order health information

Alzheimer’s Research UK has a wide range of information about dementia. Order booklets or download them from our online form.

This information was updated in March 2020 and is due for review in March 2022. It does not replace any advice that doctors, pharmacists or nurses may give you. Please contact us if you would like a version with references.

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Dementia Research Infoline

Do you have questions about dementia or want to know more about dementia research? Keen to get involved in research studies?

Contact the Dementia Research Infoline,

9am-5pm, Monday to Friday

0300 111 5 111