Young-onset dementia

These pages explains what Young-onset dementia is, including the causes and symptoms, and how it is diagnosed and treated.

What is young-onset dementia?

People with dementia whose symptoms started before they were 65 are often described as ‘younger people with dementia’ or as having young-onset dementia. The age of 65 is used because it is the age at which people traditionally retired. However, this is an artificial cut-off point without any biological significance.

The symptoms of dementia are not determined by a person’s age, but younger people often have different needs, and require some different support. This information looks at the types of dementia that younger people have, some of the difficulties they might experience and where the necessary support can be found.

Dementia in younger people

There are estimated to be at least 42,000 younger people with dementia in the UK: more than 5% of all those with dementia.

Other terms used for dementia that started before age 65 include ‘early-onset dementia’ and ‘working-age dementia’. This information refers to young-onset dementia as this is the term preferred by many people with the condition.

Young-onset dementia is caused by broadly similar diseases to dementia in older people (‘late-onset dementia’), but there are some important differences. There is a wider range of diseases that cause young-onset dementia and a younger person is much more likely to have a rarer form of dementia.

Young-onset dementia is also more likely to cause problems with movement, walking, co-ordination or balance. This is one reason why younger people with dementia may see a neurologist (a specialist in diseases of the brain and nervous system) rather than – or as well as – a psychiatrist (a specialist in mental health).

However, people under 65 do not generally have the co-existing long-term medical conditions of older people – especially diseases of the heart and circulation. They are usually physically fitter and dementia may be the only serious condition that a younger person is living with.

Young-onset dementia is more likely than late-onset dementia to be hereditary. In around 10% of all people with young onset dementia the condition seems to have been inherited from a parent. If dementia has been inherited, the diagnosis may have implications for birth relatives of the person such as their siblings (brothers and sisters) or children.