Dementia is a descriptive 'umbrella' term to describe the signs and symptoms that are caused by different diseases or conditions of the brain. Due to differing causes there are also different types of dementia, although some are far more common than others. Here you will find a simple breakdown of the most common types of dementia with links to further information.

What is dementia?

What are the most common types of dementia?

Dementia is used as an 'umbrella' term to describe the visible signs and symptoms that occur when the brain is affected by certain diseases or conditions. There are many different causes or sub-types of dementia. However, the majority of cases are due to the five most common causes of the condition. These are Alzheimer's disease, vascular dementia, dementia with Lewy bodies, mixed-dementia and frontotemporal dementia.

Understanding the specific cause or sub-type of dementia can be important as different types can be experienced and present with different signs, symptoms, rates and pattern of decline and challenges to manage and support. They can also indicate different treatments and interventions.

Below there are some brief descriptions to help you understand the different conditions or diagnosis you or the person you care for may have, with links to the Alzheimer's Society fact sheets which go into more detail.

Alzheimer's disease

Alzheimer's is the most common cause of dementia. Its onset and progression is gradual, usually presenting early with changes in memory. As the disease progresses throughout the brain the signs and symptoms become more widespread and severe affecting most areas of mental functioning. Whilst most people who experience Alzheimer's are over 65 years of age, there is a rarer 'early onset' type of Alzheimer's that can affect people before the age of 65 years of age.


Vascular dementia

Vascular dementia can occur either suddenly, following a stroke, or over time, through a series of small or 'mini' strokes'. Due to this, in contrast to AD, it can progress in a more 'step-wise' fashion with periods of stability followed by episodes of more sudden decline. As well as memory problems, depression, unsteadiness, and behaviour change can be common in vascular dementia.


Dementia with Lewy bodies (DLB)

Like Alzheimer's, DLB has a gradual onset and decline but can commonly present with features similar to Parkinson's disease following the onset of memory problems. These can include tremors and unsteady walking and/or falls. Also, hallucinations (seeing things that are not there) especially of people and animals, and disturbed sleep are also more common in this form of dementia.


Frontotemporal dementia

Frontotemporal dementia is a relatively rare type of dementia where damage is usually focused in the front part of the brain. Due to this, memory is not also affected initially but instead changes to the person's personality and behaviour can be the first signs - such as becoming indifferent to others, uninhibited and not taking care of themselves. It can affect people at a younger age, with onset happening from around 55 years of age.

Mixed dementia is becoming increasingly common and is when there is a mixture of both Alzheimer's disease and vascular dementia changes occurring in the brain, both of which contribute to changes in memory, thinking and behaviour.

Progression of dementia

Whatever type of dementia you or the person you care for has, it is progressive. This means that the structure and chemistry of the brain become increasingly damaged over time. Depending on your own circumstances and particular diagnosis, dementia and how it progresses differs from person to person. If you can view the progression of dementia as a series of stages it can be useful in helping you to understand the illness, but keep in mind that these stages will differ on an individual basis. 




Useful contacts:

Richmond Council Adult Access Team
Address: Adult Social Services, Civic Centre, 44 York Street, Twickenham, TW1 3BZ
Phone: 020 8891 7971
Minicom: 18001 020 8891 7971

Alzheimer's Society Southwest London
Phone: 020 86870922