What is Dementia and what are the different types?


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What is Dementia?

Dementia is caused by diseases that lead to the loss or death of nerve cells in the brain. Dementia is progressive, so it will develop in stages and it will get worse. Currently whilst there are treatments that help symptoms, there are is no cure. Annual statistics reported dementia is the leading cause of death in the UK. As a consequence, more and more research is going on to understand and find cures for Dementia. The most common causes are Alzheimer’s disease, Vascular Dementia and Dementia with Lewy Bodies.


Alzheimer’s is the most common cause of dementia and is thought to be present in 60% to 80% of cases. Abnormal structures called ‘plaques’ or ‘tangles’ build up inside the brain and disrupt how the nerve cells work and communicate, eventually causing them to die. The exact cause of Alzheimer’s disease is not yet fully understood but our risks of developing this increase with age, family history, untreated depression and lifestyle. There is active research continuing into the condition.

Alzheimer’s is degenerative, so it gets worse over time.

  • The first sign is usually minor memory problems like forgetting the names of places and objects or forgetting recent events.
  • Following this there may be confusion, disorientation, getting lost in familiar places, difficulty planning or making decisions, problems with speech and language and problems with daily tasks.
  • There can also be changes in personality – becoming aggressive, demanding or paranoid – and hallucinations or delusions.

Although there is currently no treatment for Alzheimer’s, it is still important to get a diagnosis so that you can plan and prepare for the future. There is also medication available that can relieve some of the symptoms and psychological treatments that support the memory, problem-solving skills and language. Alzheimer’s can cause problems swallowing which can lead to aspiration (food being inhaled into the lungs) which can cause frequent chest infections.

Vascular Dementia

Vascular Dementia is the second most common type of dementia affecting around 150,000 people in the UK. It is caused by reduced blood flow to the brain resulting in a narrowing and blockage of the small blood vessels in the brain. A single stroke or lots of mini-strokes may damage the brain and around 20% of people who have a stroke develop vascular dementia. Lifestyle factors such as smoking and being overweight or having high blood pressure or diabetes can also contribute.

Symptoms of vascular dementia include slowness of thought, difficulty planning and understanding, problems with concentration and mood or personality changes. People may also have difficulty walking and keeping balance and feel confused and disoriented.

There is currently no cure for vascular dementia, but treatment can sometimes help slow down the condition. Treatment aims to tackle the underlying cause and keeping your heart healthy is advisable. Other advice is to eat healthily, lose weight, stop smoking, get fit, cut down on alcohol and take medication to treat high blood pressure, lower cholesterol or prevent blood clots.  Psychological treatment can also help.

Dementia with Lewy Bodies (DLB)

Dementia with Lewy Bodies is caused by clumps of protein (Lewy bodies) forming inside brain cells. Lewy Bodies are also found in people with Parkinson’s disease. Why Lewy bodies develop is not understood nor is their impact on the brain. It is thought that it interferes with the messaging between brain cells.
Symptoms of DLB included problems with understanding, thinking memory and judgement, which are similar to Alzheimer’s disease, although the memory may be less affected. There may be periods of fluctuating alertness and drowsiness, which can change over hours or days. Movement may be slow and stiff with tremors, there can be fainting spells and falls. Sleep can be disturbed by violent movements and shouting.

Like vascular dementia, there is currently no cure for DLB but there are treatments that can control some of the symptoms. Treatments include medication, physiotherapy, occupational therapy, dementia activities (e.g. Memory Cafes) and psychological therapies.

Frontotemporal dementia

Frontotemporal dementia is a less common type of dementia. It is sometimes called Pick’s disease or frontal lobe dementia.  It is a significant cause of dementia in people under 65 years and is often diagnosed between 45 and 65 years of age. People with frontotemporal dementia experience changes in personality, behaviour and language, but memory is less affected.

Mixed dementia

Many people believe that a person can only have one type of dementia at the same time, but around 10% of people are diagnosed with mixed dementia. Mixed dementia is, most commonly, a combination of Alzheimer’s and vascular dementia, and, less commonly, Alzheimer’s and dementia with Lewy bodies.

Dementia in younger people

People with dementia whose symptoms started before they were 65 are described as having ‘younger-onset dementia’. There are estimated to be at least 42,000 people living with this kind of dementia in the UK. The symptoms of dementia may be similar regardless of a person’s age.

Dementia in a younger person can progress more rapidly, although this may be partly down to our perceptions – if your loved one has found it more difficult to get a timely diagnosis due to their age, their dementia may have significantly progressed by the time they are eventually diagnosed with dementia.

Mild Cognitive Impairment.

Mild Cognitive Impairment (MCI) isn’t dementia and may never lead to dementia. As the name suggests, it involves mild deterioration in cognition (the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses), but this isn’t widespread and doesn’t cause significant problems in day-to-day life.



Further information:

Alzheimer’s Society

Dementia UK

British Heart Foundation

Alzheimer’s Research UK

The Lewy Body Society

Lewy Body Dementia Association