


What is dementia?



  • memory loss
  • thinking speed
  • mental agility
  • language
  • understanding
  • judgement





  • increasing difficulties with tasks and activities that require concentration and planning
  • depression
  • changes in personality and mood
  • periods of mental confusion
  • difficulty finding the right words


How common is dementia?



Why is it important to get a diagnosis?


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Worried someone has dementia?

If someone you know is becoming increasingly forgetful, you should encourage them to see their GP to talk about the early signs of dementia. 

Dementia is a group of related symptoms that indicate problems with the brain. One of the most common symptoms of dementia is memory loss.

There are other reasons someone might be experiencing memory loss. However, if dementia is detected early, in some cases its progress can be slowed, and the person affected may maintain their mental function.

Be aware of the signs of dementia

Memory loss is one of the key symptoms, but others include:

  • increasing difficulty with tasks and activities that require concentration and planning
  • depression
  • changes in personality and mood
  • periods of mental confusion
  • difficulty finding the right words

If you know someone who is experiencing these symptoms, encourage them to see their GP as soon as possible.

Dementia is diagnosed by doctors ruling out other conditions that could cause the symptoms. A GP will run a series of tests and assessments to see if there is an alternative explanation for the problems. The doctor may also want to discuss the problems being experienced to see how they have developed over time.

Talking to someone you think has signs of dementia

Raising the issue of memory loss – and the possibility of dementia – can be a difficult thing to do. Someone who is experiencing these symptoms may be confused, worried or in denial.

To get someone talking when you're worried about their memory, the Alzheimer's Society suggests that you:

  • have the conversation in a familiar, non-threatening environment
  • explain why talking is important and say you're worried because you care
  • use examples to make things clearer: it's important not to create a sense of "blame" – for example, instead of telling someone they couldn't make a cup of tea, you could suggest that they seem to find it difficult to make a cup of tea
  • have an open conversation, and be honest and direct – for example, ask how they're feeling about their memory
  • make a positive plan of action together

You can read more tips on initiating conversations about dementia on Alzheimer Scotland

A dementia diagnosis can come as a shock, but over time some people come to view it in a positive way. This is because a diagnosis is the first step towards getting the information, help and support needed to manage the symptoms.

A diagnosis of dementia can help people with these symptoms, and their families and friends, take control, make plans and prepare for the future.

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Causes of dementia

Dementia is caused by gradual changes and damage in the brain. The most common causes of dementia include diseases in which the brain cells degenerate and die more quickly than they would as part of the normal ageing process. The changes usually happen because of a build-up of abnormal proteins in the brain.

This damage leads to a decline in a person's mental and, sometimes, physical abilities.

The abnormal proteins are different in each type of these kinds of dementia. In most cases, dementia is not inherited directly from family members. However, frontotemporal dementia can sometimes run in families.

Causes of vascular dementia

Vascular dementia is caused when the brain's blood supply is interrupted.

Like all organs, the brain needs a constant supply of oxygen and nutrients from the blood to work properly. If the supply of blood is restricted or stopped, the brain cells will begin to die, leading to brain damage.

If the blood vessels inside the brain narrow and harden, the brain's blood supply can gradually become interrupted. The blood vessels usually narrow and become hard when fatty deposits build up on the blood vessel walls, restricting bloodflow. This is called atherosclerosis, and is more common in people who have high blood pressure, type 1 diabetes and those who smoke.

Atherosclerosis in the smaller blood vessels in the brain will also cause them to clog up gradually, depriving the brain of blood. This is known as small vessel disease. 

If the brain's blood supply is interrupted rapidly during a stroke, this can also damage brain cells. 

Not everyone who has had a stroke will go on to develop vascular dementia. However, if you have had a stroke or you have been diagnosed with small vessel disease, you may have an increased risk of developing vascular dementia.

Read more about the causes of vascular dementia on Alzheimer Scotland

Causes of Alzheimer's disease

Alzheimer's disease is the most common form of dementia. In Alzheimer's, the loss of brain cells leads to the brain shrinking.

Part of the brain known as the cerebral cortex is particularly affected by this shrinkage. The cerebral cortex is the layer of grey matter covering the brain. Grey matter is responsible for processing thoughts and many of the complex functions of our brains, such as storing and retrieving memories, calculation, spelling, planning and organising.

Clumps of protein, known as "plaques" and "tangles", gradually form in the brain. The plaques and tangles are thought to be responsible for the increasing loss of brain cells. Connections between brain cells are lost and less neurotransmitter chemicals are available to carry messages from one brain cell to another. The plaques and tangles also affect the chemicals that carry messages between brain cells.

Causes of dementia with Lewy bodies

Lewy bodies are small, circular lumps of protein that develop inside brain cells. It is not known what causes them. It is also unclear how they damage the brain and cause dementia.

It's possible that Lewy bodies interfere with the effects of two of the messenger chemicals in the brain called dopamine and acetylcholine. These messenger chemicals, which send information from one brain cell to another, are called neurotransmitters.


Dementia with Lewy bodies is closely related to Parkinson's disease. This is a condition, where part of the brain becomes more and more damaged over a number of years, leading to physical symptoms, such as involuntary shaking (tremor), muscle stiffness and slow movement. A person with dementia with Lewy bodies may also develop these symptoms.

Read more about dementia with Lewy bodies

Causes of frontotemporal dementia

Frontotemporal dementia is caused by damage and shrinking in two areas of the brain. The areas of the brain affected are called the temporal lobe and the frontal lobe. This type of dementia is one of the more common types seen in people who are under 65 years of age.

In an estimated 20% of cases, people who develop frontotemporal dementia have inherited a genetic mutation from their parents.

Motor neurone disease is sometimes associated with frontotemporal dementia. It is a rare condition that damages the nervous system over time, causing the muscles to waste away.

Read more about frontotemporal dementia on Alzheimer Scotland

Less common causes of dementia

Other causes of dementia or dementia-like conditions may be treatable or non-progressive (meaning they do not continue to get worse with time). These can include:

There are also rarer causes of neurodegenerative dementia, including:

Can dementia be prevented?

There is no certain way to prevent all types of dementia.



Diet and dementia




Read more about eating healthily

How weight affects dementia risk



Read more about losing weight

Exercise to reduce dementia risk



Read more about keeping active

Alcohol and dementia




Read more about drinking and alcohol

Stopping smoking could reduce dementia risk


Quit Your Way Scotland offers advice and encouragement to help you stop smoking. You can call them on 0800 84 84 84, from 8:00am to 10:00pm, every day. Calls are free from landlines and mobiles, or visit the Quit Your Way Scotland section.


Read more about stopping smoking

Treating dementia

Most types of dementia cannot be cured and will gradually cause more severe problems.

But there are important exceptions, including dementia caused by vitamin and thyroid hormone deficiencies, which can be treated with supplements.

Some causes can be treated surgically – for example, some brain tumours, excess fluid on the brain (hydrocephalus) or head injury.

For types of dementia that involve degeneration of nerve and brain tissue, you can take action to prevent further damage. It's possible to do this by reducing dementia risk factors, such as by managing high blood pressure, high cholesterol, type 1 diabetes and stopping smoking.

For dementia that currently cannot be cured, some types of medicine may prevent symptoms getting worse for a period of time. These medicines are usually given to people in the early and middle stages of the disease, to try to maintain or improve their independence.

It is fairly common for people with dementia to have depression. If you have dementia and depression, your GP may consider prescribing an antidepressant medication, or get you an appointment with a psychiatrist who specialises in working with older people.

Perhaps the most important type of treatment for anyone with dementia is the care and support they receive from healthcare professionals, family and friends.

If you or a loved one have been diagnosed with dementia, you should start planning the future care that will be required.

Discuss the options, such as Power of Attorney, with the people concerned – your family, your GP and your local authority. Alzheimer Scotland is also a valuable source of information and support. 

Finally, there are things you or your loved one can do to maintain memory, independence and function when you have dementia.

Medicines to treat dementia

A number of medications have been shown to be effective in treating mild, moderate and severe dementia. Depending on the particular type of dementia, the severity of the condition, or any other issues observed by the doctor, you may be prescribed medications. However, not everyone will benefit from these drugs.

Aricept (donepezil) and other acetylcholinesterase inhibitors

Acetylcholinesterase inhibitors (such as galantamine, and rivastigmine) are used to treat mild to moderate Alzheimer’s disease. They can also be used to treat dementia with Lewy bodies, and can be particularly effective at treating hallucinations.

Common side effects of acetylcholinesterase inhibitors include nausea and vomiting, but these usually get better after two weeks of taking the medication.

Acetylcholinesterase inhibitors can sometimes slow down your heartbeat, so you may need to have an electrocardiogram (ECG) both before and during treatment. An ECG is a procedure that records the rhythms and electrical activity of your heart.

Memantine hydrochloride

Memantine is a medicine that works by blocking the effects of a chemical in the brain. It is used to treat severe Alzheimer’s disease, but can also be given to people with moderate symptoms if they don't respond well to acetylcholinesterase inhibitors.


Antipsychotics are medicines that are sometimes used to treat people who's behaviour is disruptive – for example, they tend to become aggressive or agitated. They are normally used for a short period of time and with caution, because they can increase the risk of cardiovascular problems, cause drowsiness and tend to make other symptoms of dementia worse.

There is some evidence that antipsychotics can cause a range of serious side effects for people who have dementia with Lewy bodies. These include:

  • rigidity
  • immobility
  • inability to communicate

In most cases, antipsychotics are only used when there are severe symptoms of challenging and disruptive behaviour that pose harm. Before being given antipsychotic drugs, the benefits and risks of treatment should be fully discussed between health and care professionals, family carers, and, if possible, with the person being prescribed the drugs.

If antipsychotics are used, they will be prescribed at the lowest possible dose and for the shortest possible time. The health of anyone taking antipsychotics needs to be carefully monitored.


Depression is an issue for many people with dementia, perhaps linked with frustrations caused by the condition.

Depression can sometimes make the memory of a person with dementia worse. Antidepressants may be prescribed.

Psychological treatments for dementia

Psychological treatments do not slow down the progression of dementia, but they can help with the symptoms.

Cognitive stimulation and reality orientation therapy

Cognitive stimulation involves taking part in activities and exercises designed to improve memory, problem-solving skills and language ability.

Reality orientation therapy reduces feelings of mental disorientation, memory loss and confusion, while improving self-esteem.



Validation therapy

Validation therapy focuses on dementia from an emotional, rather than factual, perspective. It is based on the principle that even the most confused behaviour has some meaning for the person.

For example, if someone with dementia becomes agitated at a certain point every day because they believe their mother is going to come and pick them up, telling them that their mother is no longer alive could cause them to become more agitated and distressed.

With validation therapy, the response to this situation might involve not correcting the person and accepting their concerns, but talking to them about the issue and gradually steering the conversation in another direction. In theory, this should reduce their distress, while acknowledging that their thoughts and feelings have meaning for them.

However, while validation therapy may sometimes be used as part of the treatment of someone with dementia, there is not enough evidence about the effectiveness of this approach to be certain whether it is beneficial.

Behavioural therapy

Behavioural therapy tries to find reasons for difficult behaviour. Different strategies are adopted to try to change that behaviour.

For example, a person with dementia may have a history of wandering out of their home or care centre because they feel restless. Therefore, encouraging them to take part in regular physical exercise may help to decrease their restlessness.

Behavioural therapy can be used to treat many of the behavioural problems that are associated with dementia, such as depression, aggression and delusional thinking. Behavioural therapy is often given by a trained friend or relative (usually the main family carer), or by an employed carer, but is supervised by a healthcare professional.

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Can dementia be cured?

The concept that dementia is a disease rather than an inevitable side effect of ageing (so-called senile dementia) has been around for over 100 years.

But after over a century of research, there's still a lot we don't know about the condition and if dementia can be cured.

Dementia charities have argued, with some justification, that there is a lack of funding for research into dementia compared with research into treatments for other long-term conditions, such as cancer.

However, many areas of research may lead to more effective treatments and, possibly, a cure for dementia. Inevitably, such treatments are many years, probably decades, of hard work away.

Even without a cure, there is reason to believe that a continuous improvement in the standards of dementia care can be achieved.  

Here are some of the current promising areas of dementia research.

Gene therapy for dementia

Gene therapy is a field of medicine where genetic material is used to try to prevent or cure a disease.

While the theory behind gene therapy has been discussed since the 1970s, this is a very new area of research, and there is currently only one licensed treatment available in the UK.

In dementia, gene therapy aims to stop brain cells dying, or possibly replace them, but it may be several years before human trials can begin.

Dementia vaccine

Some researchers are studying what has been termed a dementia vaccine. This would be a medication to "teach" the immune system to recognise the abnormal deposits of protein (such as amyloid plaques) in Alzheimer's disease that are thought to cause the damage to brain cells.

The immune system would then attack these plaques, which may slow the progression of the condition. Researchers are studying several different ways of doing this, ranging from vaccines to infusions of antibodies.

Stem cells and dementia

Stem cells are "building block" cells. They can develop into many different cell types, including brain cells.

Two main avenues of research into the use of stem cells in dementia are being explored.

First, stem cells can be manipulated so they mimic some of the body's processes that may cause the development of dementia. Doing this will help scientists to better understand dementia. It also allows researchers to predict the effects of potential dementia drugs more accurately.

Second, researchers hope that one day, stem cells could be used to develop new brain cells to replace the cells that are damaged by dementia.

Psychological interventions for dementia

These advances in complex technology are important, but there have also been developments in helping people to deal with their psychological symptoms. These include:

  • cognitive stimulation – where people take part in activities and exercises designed to improve their memory, problem-solving skills and language ability
  • validation therapy – where people are encouraged to explore what things were like for the person in the past and how this relates to the way they are feeling now

Research into improving these approaches continues, and other new approaches are also being explored. These include social media support groups and memory improvement apps.

Another goal of research into psychological interventions is to find ways to help manage challenging behaviour in people with dementia without having to resort to antipsychotic medicines.

One method that is providing promising results is known as functional analysis. This is based on the theory that the best way to manage challenging behaviour is to understand the motivation driving it. People with dementia often act in challenging ways because they feel their needs are not met, and that makes them upset.

Join dementia research

There are dozens of dementia research projects going on around the world; many of these are based in the UK. You may be able to help scientists better understand the disease by taking part in research.

This includes studies looking at how our genes, or even our lifestyle, may play a role in our risk of developing dementia.
