While Alzheimer's disease is the most common form of dementia, there are also other common types such as vascular dementia, Lewy body dementia and Frontotemporal dementia. There are also rarer types of dementia that are caused by other diseases and conditions.
Some people develop multiple types of dementia; this is known as mixed dementia. It is also possible for a younger person to develop dementia. When a person develops dementia before the age of 65, this is known as young-onset dementia.
In the UK, about 1 in 20 people living with dementia have a rarer type.
Rarer causes of dementia include:
- Atypical Alzheimer’s disease
- Frontal variant Alzheimer’s disease (fvAD),
- Posterior cortical atrophy (PCA)
- Corticobasal syndrome (CBS)
- Creutzfeldt–Jakob disease (CJD)
- HIV-associated neurocognitive disorder (HAND)
- Huntington’s disease
- Normal pressure hydrocephalus (NPH)
- Progressive supranuclear palsy (PSP)
People with learning disabilities, particularly those with Down's syndrome, are at increased risk of developing dementia. If a person with a learning disability develops dementia, they will face different and additional challenges to people who do not have a learning disability.
Around a third of people with Parkinson’s eventually develop dementia.
The disease that causes Parkinson’s is very similar to the one that causes dementia with Lewy bodies.
Mild cognitive impairment (MCI) is a condition in which someone has minor problems with cognition - their mental abilities such as memory or thinking. It is not a type of dementia, but a person with MCI is more likely to go on to develop dementia.
What is dementia?
The word 'dementia' describes a set of symptoms. It is caused by different diseases in the brain.