Dementia is a condition of the brain which causes a gradual loss of mental ability, including problems with memory, understanding, judgement, thinking and language. It can also lead to changes in personality and the way a person interacts with others in social situations. As dementia progresses, it may affect a person's ability to look after themselves.
One common symptom is memory loss. This could include problems remembering recent events, such as forgetting messages, remembering routes or names, or asking the same questions repeatedly. Occasional examples of this need not be alarming, as they can be a natural part of getting older, but if they do become more frequent, it’s important to seek medical advice.
Other symptoms may include:
- finding it difficult to organise or plan simple tasks
- becoming confused in unfamiliar environments
- difficulty in finding the right words
- finding it hard to deal with numbers, including handling money in shops
- forgetting about recent conversations or events
- becoming slower at grasping new ideas
- showing poor judgement, or find it harder to make decisions
- losing interest in other people or activities
- unwilling to try out new things or adapt to change
- becoming depressed
- noticing a change in personality
Causes of dementia
Dementia can be caused by various diseases or disorders which affect the parts of the brain involved with thought processes. The most common types are Alzheimer's disease, vascular dementia, dementia with Lewy bodies (DLB) and Fronto-temporal dementia.
This is the most common type of dementia, causing 62 per cent of all cases. It is named after the doctor who first described it. In Alzheimer's disease the brain shrinks and the numbers of nerve fibres in the brain gradually reduce. Some of the brain chemicals, which help to send messages between brain cells, also reduce and tiny deposits called plaques form throughout the brain. It is not known why these changes in the brain occur, or exactly how they cause dementia.
Vascular dementia, or blood vessel dementia, is the cause of 17 per cent of cases. A reduction in blood flow to the brain, often as a result of a stroke or a series of small strokes, leads to the brain cells being deprived of oxygen and dying. This can occur in distinct parts of the brain, leaving other areas relatively unaffected.
Dementia with Lewy bodies
Dementia with Lewy bodies is the third most common cause of dementia, causing around
Fronto-temporal dementia (originally called Pick’s disease) is a common cause of dementia in people under the age of 65 and can affect a person’s personality or behaviour. This type of dementia is caused by damage to areas of the brain responsible for behaviour, emotional responses and language.
Who gets dementia?
Unfortunately we don’t know why some people develop dementia and others don’t. What we do know is that several things can affect your risk of developing dementia, including your age, health and lifestyle.
The older you are, the higher your chance of developing dementia. Between the age of 65 and 74, one or two people in 100 will have dementia. By the age of 95, a quarter of people will have it. However, dementia is not a normal part of ageing. It’s different to the age-associated memory impairment that is common in older people.
Dementia rarely affects younger people and is said to be early-onset if it occurs before the age of 65. Some people are known to have a higher risk of dementia, including people with Down’s syndrome or Parkinson's disease. High blood pressure, smoking, high cholesterol levels and lack of exercise can all increase your risk of developing dementia.
Dementia is not an inherited disease, however there is a small extra risk of getting dementia if you have a mother, father or sibling with dementia.
Reducing the risk of dementia
To reduce the risk of developing dementia and other serious health conditions, it's recommended that you:
- eat a healthy diet
- maintain a healthy weight
- exercise regularly
- don't drink too much alcohol
- stop smoking (if you smoke)
- make sure to keep your blood pressure at a healthy level.
Free online cognitive function test
A new, free online cognitive function test has been developed for people over 50. The 20 minute quiz assesses a middle aged person’s chance of suffering from the brain condition and gives advice on how to stay healthy and help reduce the risk of Alzheimer’s disease.
The questions have been developed with the help of one of Britain’s leading authorities on Alzheimer’s, Professor David Smith from Oxford University, and charity www.foodforthebrain.org
It is hoped the results of people taking the test will eventually provide vital information for a national prevention strategy.
Help is out there
If you are concerned that you or a friend or relative has dementia, it’s important that you talk to your GP. You can also find information, advice and support in your area via the following websites: