What is Dementia?

Dementia is an umbrella term for a number of different progressive disorders of the brain which share common symptoms such as:

  • memory loss
  • confusion
  • disorientation
  • problems with speech and understanding.

Dementia can affect people from all walks of life and will affect people in different ways. As dementia is a progressive illness, it will affect you more over time. There are currently about 850,000 people in the UK diagnosed with a form of dementia. However, your journey with dementia will be individual to each person

Dementia becomes increasingly common with age but it is not a natural part of growing old. It is important to be aware that dementia is an illness. No one is to blame and support is available.

There are a number of different types of dementia:


1. Alzheimer’s Disease

Alzheimer‘s disease is the most common form of dementia and accounts for around 520,000 cases in the UK. Alzheimer’s disease is caused when protein plaques and tangles form in the brain, leading to the death of brain cells. People with Alzheimer’s disease have a shortage of some important chemicals in their brain which send messages within the brain. There tends to be a gradual, sloped progression of the disease and changes tend to develop steadily over a period of time.


2. Vascular Dementia

Vascular dementia is the second most common form of dementia. It is caused by problems in blood supply to the brain. Symptoms may develop suddenly, for example, following a stroke or more gradually, such as with small vessel disease or a series of mini strokes (TIAs). It usually has a stepped progression with symptoms remaining at a constant level for some time and then suddenly deteriorating. People who have vascular dementia often report having good days and bad days and can be more prone to mood swings and depression.


3. Parkinson‘s Dementia & Dementia with Lewy Bodies

These are the two forms of dementia associated with Parkinson’s disease:

  • Parkinson‘s dementia is diagnosed when someone already has the movement symptoms of Parkinson‘s and has had them for some time.
  • Dementia with Lewy Bodies is diagnosed when someone has the symptoms of dementia either before or at the same time as they develop Parkinson‘s.

People with these types of dementia may be likely to experience visual hallucinations as well as forgetfulness, slow thought processes and difficulty concentrating.


4. Frontotemporal Dementia

Frontotemporal dementia is a relatively uncommon form of dementia, although it is a significant cause of dementia in people under the age of 65. Frontotemporal dementia is sometimes called Pick‘s disease or frontal lobe dementia. It is caused by damage to the frontal and / or the temporal lobes of the brain. These areas are responsible for many functions including our behaviour, emotional responses and language skills.


5. Other Types of Dementia

Mixed dementia is a term that describes changes in the brain that are caused by two different forms of dementia. The mix is most commonly Alzheimer‘s disease and vascular dementia but can sometimes be a mix of other types of disease.

Alcohol-related dementia and Korsakoff’s Syndrome are both brain disorders associated with heavy alcohol consumption over a long period of time. Korsakoff’s syndrome mainly affects the short term memory whereas people with alcohol-related dementia may experience a more varied set of symptoms. People with alcohol-related dementia could see an improvement in the condition if they stop drinking alcohol.


Related Conditions

Mild Cognitive Impairment (MCI) is a condition where a person has minor problems with memory or thinking. MCI is not a type of dementia. Difficulties diagnosed and related to MCI are worse than would normally be expected for a healthy person of their age. MCI symptoms are not severe enough to interfere significantly with daily life and are not defined as dementia.

A diagnosis of MCI, does not mean a person will later develop dementia, although there is a greater chance that someone with MCI will develop dementia. Research studies have shown only 10-15 percent of people with MCI develop dementia, so there is benefit in a MCI diagnosis, seeking support and making necessary lifestyle changes.


If you or someone you care for has a diagnosis of dementia and you would like more information on what it means in your case, speak to your GP, a specialist or an advisor from the Bromley Dementia Support Hub. They may have already explained things when giving you your diagnosis. Perhaps you weren‘t able to take all of the information in. If so, feel free to ask again, make your own notes, go with a close friend or family member so that it is easier to remind yourself of the information later.



  • You are not alone
  • Dementia will affect different people in different ways
  • Ask your GP or specialist for more information.


More Living with Dementia Articles

This article is part of a series of articles called Living with Dementia. They are for Bromley residents and are being published one a week between 15th May and 3rd July 2017. See more Living with Dementia articles as they are published here.