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What is Dementia

What is dementia?

Learn more about dementia, common signs and symptoms, and how to live well following a diagnosis

Dementia is a set of symptoms caused by damage to the brain from certain diseases or conditions. Dementia usually gets worse over time and there is currently no cure. Symptoms can include problems with memory, thinking, mental agility, language and understanding. Dementia is common, and as people live longer more people have family and friends who are living with dementia.

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Types of dementia

There are around 100 conditions which cause dementia. Some types are more common than others.

Alzheimer's disease

causes damage to brain cells. It is the most common cause of dementia, accounting for around two thirds of cases.

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Vascular dementia

is the second most common type of dementia. It is caused by a reduced blood supply to the brain due to conditions such as high blood pressure, stroke or irregular heart rhythms.

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Dementia with Lewy Bodies

accounts for around 10 percent of cases. Lewy bodies are tiny deposits of protein that can build up in the cells of the brain and cause damage.

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Frontotemporal dementia

is caused when abnormal proteins in the brain cause damage to brain cells.

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Posterior Cortical Atrophy

is a form of Alzheimer’s disease which causes damage to the brain cells at the back of the brain (posterior). This part of the brain is vital for judging space and distance, and for making sense of what we see.

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HIV associated dementia

affects around 50 percent of people with the Human Immunodeficiency Virus (HIV). HIV can also affect brain function and motor skills.

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Parkinson’s with dementia

is a condition that some people experience in the later stages of Parkinson’s disease. It is thought to be caused by a build-up of Lewy bodies in brain cells.

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Korsakoff’s syndrome

is a type of a dementia that does not get worse over time. It is usually caused by excessive alcohol consumption.

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Mixed dementia

is when someone has more than one type of dementia. It is common to have both Alzheimer’s disease and vascular dementia together.

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Signs and Symptoms

Dementia affects everyone differently. However, common symptoms in the early stage of dementia include:

  • difficulties with short-term memory – losing things, forgetting peoples’ names or the names of everyday objects
  • language difficulties and struggling to follow conversations
  • problems with spatial awareness – difficulty parking, crossing roads, judging distances or the size and shape of objects
  • feeling confused or disorientated
  • difficulty concentrating
  • difficulties with planning and organising – not turning up to routine appointments or struggling to do everyday tasks
  • changes in mood and behaviour
  • sleep disturbances
  • changes to appetite
  • problems with vision – failing to spot things that are close by, or being unable to tell coins and notes apart when handling money

The different types of dementia have different symptoms and progress in different ways. For example, Alzheimer’s disease tends to progress gradually, whilst people living with vascular dementia can have long periods where symptoms are stable followed by periods where symptoms rapidly get worse.

Risk factors

Many people think that if their parents had dementia, then they will get it too. Certain genes can increase the risk slightly, and some forms of Alzheimer’s disease are genetic and passed through family, however these are very rare. There is a link between severe or repeated head injury and dementia.

The biggest risk factor for dementia is age, particularly for those over the age of 65. More than two thirds of people living with dementia are female.

Reducing your risk

You may have seen stories in the media claiming a cure for dementia is just around the corner. Many different treatments are currently being investigated. However, it is likely to be several years or even decades before a cure is found. The good news is, while it's not possible to entirely prevent dementia, there are things you can do to reduce your risk of developing it. What is good for your heart is also good for your head, so eating a balanced diet and doing regular physical activity are very important. Stopping smoking and reducing alcohol consumption can help as well. 

More information

For more information about reducing risk, read Age Scotland’s guide to Reducing your Risk of Dementia.

What else can affect memory or thinking skills?

Many people think that dementia is memory loss, and memory loss is dementia, but being forgetful doesn’t necessarily mean someone has dementia. A slight decline in memory is normal as people age, but a lot of things can affect your memory:

  • Physical health problems can affect memory and thinking, include stroke, infections, thyroid problems, nutritional deficiencies and diabetes. Not drinking enough fluids, the side effects of medicines, smoking, drinking alcohol heavily and not sleeping well can have an impact too.
  • Mental health problems including stress, depression, anxiety or grief can cause memory and thinking problems. Our guide Mental health and wellbeing – keeping well and who can help provides information about staying mentally well.
  • Changes to senses as people get older may seem like problems with memory, when in fact changes to the senses are getting in the way of remembering. Most people can bring back memories through their senses, for example looking at a photograph, listening to a piece of music or smelling familiar food.
  • Mild cognitive impairment is a medical diagnosis which is not the same as regular ageing, but not dementia. This diagnosis is given when someone has problems with memory or thinking beyond what can be expected because of normal ageing. Mild cognitive impairment is usually stable and can sometimes get better if it is related to a treatable illness such as depression. People with mild cognitive impairment are at greater risk of developing dementia than the general population, so it is important that they have regular medical checks and appropriate treatment.

What if it is dementia?

People react in different ways to a dementia diagnosis. A diagnosis might be a relief to some or make others shocked, sad, fearful or angry. There is no right or wrong way to feel. There are a lot of organisations that can support you and help you plan for the future. With the right support in place, many people with dementia can live well and lead fulfilling lives for many years.

More Information

For more information, see Age Scotland’s guides Living Well With Early-Stage Dementia and Caring for Someone With Early-Stage Dementia.

Dementia resources

Find out more about Age Scotland's work and services to support people affected by dementia.

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