What is Dementia?
What is Dementia?
What is Dementia
Dementia is an umbrella term for a number of progressive conditions affecting memory, thinking, problem-solving and language. It is caused by diseases which damage brain cells and interfere with the normal workings of the brain.
Each person affected by dementia will experience it differently, depending on the cause, on which parts of their brain is affected as the condition progresses, and of course, their own personality and circumstances.
Different types of dementia have different causes. Alzheimer’s disease is the most common type, followed by vascular dementia, dementia with Lewy bodies and fronto-temporal dementia. There are a large number of less common forms of dementia and some people have more than one form at the same time, known as ‘mixed dementia’.
According to Alzheimer’s Research UK there are around 820,000 people living with dementia in the UK. The majority are older people, and incidence increases with age, with one in 20 over the age of 75, and one in five over the age of 85, affected. Although the likelihood of being affected increases with age, dementia is not a normal part of ageing. It is also possible for younger people to have dementia, and dementias that are diagnosed before the age of 65 are known as ‘early-onset’.
Common types of dementia
Alzheimer’s disease − the most common cause of dementia. During the course of the disease the chemistry and structure of the brain changes, leading to the death of brain cells. Problems of short-term memory are usually the first noticeable sign.
Vascular dementia − if the oxygen supply to the brain fails due to vascular disease, brain cells are likely to die and this can cause the symptoms of vascular dementia. These symptoms can occur either suddenly, following a stroke, or over time through a series of small strokes. Vascular dementia and Alzheimer’s disease frequently occur together, and they may often act in combination to cause dementia.
Dementia with Lewy bodies − this form of dementia gets its name from tiny abnormal structures that develop inside nerve cells. Their presence in the brain leads to the degeneration of brain tissue. Symptoms can include disorientation and hallucinations, as well as problems with planning, reasoning and problem solving. Memory may be affected to a lesser degree. This form of dementia shares some characteristics with Parkinson’s disease.
Fronto-temporal dementia (including Pick’s disease) − in fronto-temporal dementia, damage is usually focused in the front part of the brain. This damage causes the typical symptoms which include changes in personality and behaviour and difficulties with language.