Why the type matters
Dementia is an umbrella term. Underneath it are different diseases that damage the brain in different ways. Each one tends to cause a slightly different pattern of symptoms, especially early on.
Knowing the type can help:
- explain why a person is having particular difficulties
- guide which medicines may help, and which to avoid
- point families to the right information and support
- help with planning, because some types change in different ways over time
Sometimes the type is clear. Sometimes specialists need scans or more detailed tests. And sometimes a person has more than one type. See getting a diagnosis.
The main types compared
This table gives a simple overview. Not everyone will have every symptom, and symptoms often overlap.
| Type | What happens in the brain | Common early signs | How common |
|---|---|---|---|
| Alzheimer’s disease | Amyloid plaques and tau tangles damage brain cells | Forgetting recent events, repeating questions, word-finding problems | Most common: about two in three people with dementia in the UK (Alzheimer’s Society) |
| Vascular dementia | Reduced blood flow damages brain tissue | Slow thinking, trouble planning and concentrating, mood changes | Second most common: around 180,000 people in the UK (NHS) |
| Dementia with Lewy bodies | Clumps of protein (Lewy bodies) inside brain cells | Alertness that varies, seeing things that are not there, slow movements, acting out dreams | Around 5% of people with a dementia diagnosis are recorded as having it, but it is thought to be under-diagnosed |
| Frontotemporal dementia | Damage to the front and sides of the brain | Changes in personality and behaviour, or language problems | Less common; mostly diagnosed between 45 and 65 (NHS) |
Mixed dementia
Mixed dementia means having more than one type of dementia at the same time. Alzheimer’s Society says it affects at least 1 in 10 people diagnosed with dementia.
The most common mix is Alzheimer’s disease with vascular dementia. A person may have memory problems from Alzheimer’s disease along with slower thinking and trouble concentrating from blood vessel damage.
Symptoms depend on which types are present and how much each one is affecting the brain. Treatment is usually based on the types involved. For example, Alzheimer’s medicines may be considered if Alzheimer’s disease is part of the picture.
Young-onset dementia
Young-onset dementia is not a separate disease. It means any type of dementia where symptoms start before the age of 65. Younger people are more likely to have rarer types, such as frontotemporal dementia. They also face particular issues with work, family and money. See young-onset dementia.
Rarer types of dementia
Alzheimer’s Society says about 1 in 20 people living with dementia in the UK have a rarer type. These include:
- Posterior cortical atrophy (PCA): usually a form of Alzheimer’s disease that affects the back of the brain first. Early problems are often with vision, such as reading or judging distances, even though the eyes are healthy.
- Parkinson’s disease dementia: thinking problems that develop in people who have had Parkinson’s disease for some time. It is closely linked to dementia with Lewy bodies.
- Progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS): conditions affecting movement, balance and thinking.
- Huntington’s disease: caused by a faulty gene, affecting movement, thinking and mood.
- CADASIL: an inherited condition affecting small blood vessels in the brain.
- Creutzfeldt-Jakob disease (CJD): a very rare brain disease that gets worse quickly.
- HIV-associated neurocognitive disorder (HAND): thinking problems linked to HIV.
- Normal pressure hydrocephalus (NPH): a build-up of fluid in the brain, which can sometimes be treated.
Alcohol-related brain damage
Long-term heavy drinking can damage the brain. This is called alcohol-related brain damage (ARBD). One severe form is Wernicke-Korsakoff syndrome, which is linked to a lack of thiamine (vitamin B1).
Alzheimer’s Society explains that ARBD is different from most dementias because it does not always get worse. With support to stop drinking, some people make a partial or even full recovery. It is often diagnosed between the ages of 40 and 60.
Early symptoms by type
The first symptoms can be a clue to the type of dementia, but only a specialist can make a diagnosis.
| First changes noticed | Types to consider |
|---|---|
| Memory for recent events | Alzheimer’s disease, mixed dementia |
| Slow thinking, planning problems, stroke-like symptoms | Vascular dementia |
| Hallucinations, varying alertness, movement changes | Dementia with Lewy bodies |
| Personality, behaviour or language changes | Frontotemporal dementia |
| Vision and reading problems with healthy eyes | Posterior cortical atrophy |
What to do next
If you have noticed changes in yourself or someone close to you, start with the GP. Many other conditions can cause similar symptoms, and some are treatable. Read about early signs and other causes of memory loss.
If a diagnosis has already been made, ask the memory service to explain the type in writing. For support, see support and helplines.