What is Dementia?


The word ‘dementia’ describes a set of symptoms that may include memory loss and difficulties with thinking, problem-solving or language. These changes are often small to start with, but for someone with dementia they have become severe enough to affect daily life. A person with dementia may also experience changes in their mood or behaviour.


Dementia is caused when the brain is damaged by diseases, such as Alzheimer’s disease or a series of strokes. Alzheimer’s disease is the most common cause of dementia, but not the only one. The specific symptoms that someone with dementia experiences will depend on the parts of the brain that are damaged and the disease that is causing the dementia.

What are the most common forms of dementia?


The different types of dementia tends to affect people differently, especially in the early stages. Other factors that will affect how well someone can live with dementia include how other people respond to them and the environment around them.

Dementia is progressive, which means the symptoms gradually get worse over time. How quickly this happens varies greatly from person to person. As dementia progresses, the person may develop behaviours that seem unusual or out of character. These behaviours may include asking the same question over and over, pacing, restlessness or agitation. They can be distressing or challenging for the person and those close to them.

A person with dementia will have cognitive symptoms (to do with thinking or memory). They will often have problems with some of the following:

Day-to-day memory – difficulty recalling events that happened recently.

Concentrating, planning or organising – difficulties making decisions, solving problems or carrying out a sequence of tasks (such as cooking a meal)

Language – difficulties following a conversation or finding the right word for something

Visuospatial skills – problems judging distances (such as on stairs) and seeing objects in three dimensions

Orientation – losing track of the day or date, or becoming confused about where they are.

A person with dementia will also often have changes in their mood. For example, they may become frustrated or irritable, apathetic or withdrawn, anxious, easily upset or unusually sad. With some types of dementia, the person may see things that are not really there (visual hallucinations) or strongly believe things that are not true (delusions). A person with dementia, especially in the later stages, may have physical symptoms such as muscle weakness or weight loss. Changes in sleep pattern and appetite are also common.

Causes of dementia


Alzheimer’s disease – This is the most common cause of dementia. In Alzheimer’s disease, an abnormal protein surrounds brain cells and another protein damages their internal structure. In time, chemical connections between brain cells are lost and cells begin to die. Problems with day-to-day memory are often the first thing to be noticed, but other symptoms may include difficulties finding the right words, solving problems, making decisions, or perceiving things in three dimensions.

Vascular dementia – If the oxygen supply to the brain is reduced because of narrowing or blockage of blood vessels, some brain cells become damaged or die. This is what happens in vascular dementia. The symptoms can occur suddenly, following one large stroke. Or they can develop over time, because of a series of small strokes. Vascular dementia can also be caused by disease affecting the small blood vessels deep in the brain, known as subcortical vascular dementia. The symptoms of vascular dementia vary and may overlap with those of Alzheimer’s disease. Many people have difficulties with problem-solving or planning, thinking quickly and concentrating.

They may also have short periods when they get very confused. Mixed dementia – This is when someone has more than one type of dementia, and a mixture of the symptoms of those types. It is common for someone to have both Alzheimer’s disease and vascular dementia together.

Dementia with Lewy bodies – This type of dementia involves tiny abnormal structures (Lewy bodies) forming inside brain cells. They disrupt the chemistry of the brain and lead to the death of brain cells. Early symptoms can include alertness that varies over the course of the day, hallucinations, and difficulties judging distances.

A person’s day-to-day memory is usually affected less than in the early stages of Alzheimer’s disease. Dementia with Lewy bodies is closely related to Parkinson’s disease and often has some of the same symptoms, including difficulty with movement. Frontotemporal dementia (including Pick’s disease) – In frontotemporal dementia, the front and side parts of the brain are damaged. Clumps of abnormal proteins form inside brain cells, causing them to die. At first, changes in personality and behaviour may be the most obvious signs. Depending on which areas of the brain are damaged, the person may have difficulties with fluent speech or forget the meaning of words. The symptoms of these types of dementia are often different in the early stages but become more similar in the later stages. This is because more of the brain is damaged as the different diseases progress. In the later stages of dementia, the person will need more and more support to carry out everyday tasks. However, many people with dementia live well for years after their diagnosis. Information, advice and support are available for the person and their carer to help them live well with dementia.

Treatments for dementia


The vast majority of causes of dementia cannot be cured, although research is continuing into developing drugs, vaccines and other medical treatments. Here we outline the many things that can be done to enable someone with dementia to live well with the condition.


Care and support for someone living with dementia should always be ‘person-centred’. This means it should be focused on that person and their individual needs and preferences.

Non-drug treatments and support

There are a range of non-drug treatments available that can help someone to live well with dementia. These include information, advice, support, therapies and activities. The GP, memory service or local Alzheimer’s Society are good places to start for more information on what is available. Support for the person and their carer should be available after a diagnosis. This should give them the chance to talk things over with a professional, ask questions about the diagnosis, and think about the future. It’s also important to get information on planning ahead, where to get help with this and how to stay well, both physically and mentally.

Other types of treatment include the following:

Talking therapies, such as counselling, can help someone come to terms with their diagnosis or discuss their feelings. Cognitive behavioural therapy (CBT) may be offered if the person develops depression or anxiety.

Cognitive stimulation therapy is a popular way to help keep someone’s mind active. It involves doing themed activity sessions over several weeks.

Cognitive rehabilitation can enable an individual to retain skills and cope better. There is also lots that can be done at home to help someone with dementia remain independent and live well with memory loss. Support ranges from devices such as pill boxes or calendar clocks to practical tips on how to develop routines or break tasks into simpler steps.

Many people with dementia enjoy life story work, in which the person is encouraged to share their life experiences and memories. As a person’s dementia progresses, the may also enjoy reminiscence work. Such activities may help improve someone’s mood, wellbeing and mental abilities.

Other popular activities include music, singing or art. It is vital that people with dementia stay as active as they can – physically, mentally and socially. Taking part in meaningful activities is enjoyable and leads to increased confidence and self-esteem.

Drug treatments

There are drugs that can help with the symptoms of dementia , or that in some cases may stop them progressing for a while.

A person with mild to moderate Alzheimer’s disease or mixed dementia in which Alzheimer’s is the main cause may be prescribed one of three different drugs: donepezil, rivastigmine or galantamine. These may give temporary help with memory, motivation, concentration and daily living. In the moderate or severe stages of Alzheimer’s disease someone may be offered a different drug called memantine. This may help with attention and daily living, and possibly ease distressing or challenging behaviours.

Donepezil, rivastigmine and galantamine can also be helpful for someone with dementia with Lewy bodies who has distressing hallucinations or delusions, or who has behaviours that challenge (for example, agitation or aggression).

For a person with vascular dementia, drugs will be offered to treat the underlying medical conditions that cause dementia. These conditions often include high blood pressure, high cholesterol, diabetes or heart problems. Controlling these may help slow the progression of dementia.

A wide range of other drugs may be prescribed at different times for a person with dementia. These include drugs for depression or anxiety, sleeping tablets or antipsychotics. Note that some of these drugs can have severe side effects.

Not all are recommended for all types of dementia. Health professionals will generally recommend that a non-drug approach is tried first before prescribing medication, unless a person’s symptoms are very severe.

Can dementia be prevented?


It is not usually possible to say for sure why a particular person has developed dementia. Ageing is the biggest risk factor for dementia and can’t be changed. There are however lots of things you can do to reduce your risk.


What risk factors can we change?

Factors such as high blood pressure, lack of physical exercise and smoking – all of which lead to narrowing of the arteries – increase the risk of developing Alzheimer’s disease and vascular dementia. There is evidence that a healthy lifestyle, especially in mid-life, can help reduce the risk of dementia. Regular physical exercise (for example, cycling, swimming, brisk walking), maintaining a healthy weight, not smoking, and drinking alcohol only in moderation, if at all, are linked to a reduced risk of dementia.

A healthy balanced diet also helps to reduce a person’s risk. A balanced diet is one which is low in saturated fat, does not have too much salt, sugar or red meat, and includes plenty of fish, starchy foods, and fruit and vegetables. All these healthy lifestyle choices will also reduce the risk of other serious conditions such as stroke, heart disease and cancer.

A person who is already living with conditions such as diabetes, heart problems, high blood pressure or high cholesterol should follow professional advice to keep their condition under control. Getting depression treated early is also important.

It also seems that keeping mentally and socially active into later life may help lower a person’s risk of dementia. Being mentally active could include doing puzzles or reading, or learning a new skill. Being socially active could include visiting friends or going to a place of worship. Volunteering could offer both mental and social activity and many organisations offer opportunities for people looking to donate their time or skills.