Dementia explained

Expert reviewer Professor Graham Stokes, Bupa Global Director of Dementia Care
Next review due November 2019

Dementia is not one medical condition, but a set of symptoms. Common causes, or ‘types,’ of dementia include Alzheimer’s disease and vascular dementia.

Dementia is closely linked to age, but it’s not an inevitable part of growing old.

Dementia symptoms become worse over time and people often end up in residential care. There is no cure for dementia.

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About dementia

The main symptoms of dementia are:

  • difficulties with remembering, thinking and language
  • difficulties with daily activities
  • emotional and behavioural difficulties

The exact dementia symptoms someone has will depend on the type of dementia, especially in the early stages.

Dementia can have a significant effect on a person with the condition, including:

  • associated health problems
  • being dependent on others for complex matters like financial affairs, and eventually personal care as the dementia symptoms worsen
  • It can also have a significant effect on someone who cares for a friend or relative with dementia.

People are used to hearing dementia explained in negative terms. It is true that dementia presents significant challenges, but there are ways for a person to live well with dementia. These include:

  • staying physically and mentally active
  • developing coping strategies
  • people communicating with them in a certain way
  • the physical environment being adapted for them
  • their community being ‘dementia-friendly’ and inclusive

What does 'dementia' mean?

Dementia is not just one specific medical condition. The word actually refers to a set of symptoms. These dementia symptoms include problems with thinking, reasoning, learning, memory and language, and difficulties with daily activities.

This set of dementia symptoms can be caused by a number of different underlying conditions. Although technically these conditions cause dementia, they’re often referred to as different ‘types’ of dementia. You may have heard of some of the most common ones. They include:

  • Alzheimer’s disease – This is the most common type of dementia. Parts of the brain shrink and certain proteins build up in the brain. The early signs of Alzheimer's disease are usually memory lapses, and the condition steadily gets worse over time.
  • Vascular dementia – This is the second most common type of dementia. The first vascular dementia symptoms often appear after a stroke or ‘mini-stroke’. Over time vascular dementia gets worse, usually in big noticeable ‘steps’, rather than gradually. This means a person's dementia symptoms may worsen quickly and unexpectedly.
  • Dementia with Lewy bodies – This is caused by certain proteins building up in nerve cells. In additional to common dementia symptoms, people with dementia with Lewy bodies may experience hallucinations, or movement problems similar to Parkinson’s disease.
  • Frontotemporal dementia – This is a rare type of dementia that is caused when cells die in specific parts of the brain. Unlike other forms of dementia, frontotemporal dementia usually starts with personality and behavioural symptoms, rather than memory difficulties.

What does dementia mean? For most people, dementia means that they have one of the four conditions described above. There are also some other types of dementia, but these are very rare.

Dementia is closely linked to age. It is very unusual to experience any dementia symptoms before the age of 65. After this, the risk increases steadily as you get older. It can be frightening to hear dementia explained in this way, but you should know that dementia is not inevitable when you get older.

There’s a difference between the usual mild memory loss that occurs as you age, and dementia. If you just occasionally have trouble remembering things, this is unlikely to mean that you are experiencing dementia symptoms.

Dementia gets worse over time. Problems will be quite mild to start with, but will eventually become more severe and disrupt the person’s daily life. A person with dementia often ends up needing residential care.

Sadly there is no cure for dementia. There are a handful of treatments that can slow down the progression of symptoms in the early and middle stages of Alzheimer’s disease.

Symptoms of dementia

Dementia has lots of possible symptoms. These will depend on the person and the type of dementia. The main dementia symptoms are outlined here:

Difficulties with remembering, thinking and language

  • memory problems like forgetfulness, repeating the same question, difficulty finding the right word
  • difficulty reading or following a conversation
  • being disorientated
  • struggling with things like laying the table, telling the time, or understanding instructions

Difficulties with daily activities

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  • getting lost in familiar places
  • problems with domestic routine, like forgetting a recipe or neglecting chores
  • developing unhygienic habits or neglecting appearance

Emotional and behavioural difficulties

  • being withdrawn or apathetic
  • feeling low or anxious
  • appearing suspicious
  • being irritable and aggressive
  • restlessness or trouble sleeping

Different types of dementia tend to cause different symptoms and emotional reactions, particularly in the early stages. For example, in Alzheimer’s disease the early symptoms tend to involve memory problems, whereas in dementia with Lewy bodies someone may experience hallucinations or physical symptoms. However, as the conditions progress, all dementia types tend to ‘converge’ in terms of symptoms. So someone in the later stages will have a wider range of the symptoms above, no matter what type of dementia they have.

You can find out more about which symptoms are associated with which types of dementia in our section on types of dementia.

How dementia affects people

What does a diagnosis of dementia mean for you or your loved one? Because of its wide-ranging symptoms, dementia has a significant effect on people who have the condition, and those who need to care for and support them.

Other health problems

Depending on the type of dementia someone has, they may be at risk of developing other health problems, for example infections or pneumonia. There is more information on this in our section on types of dementia.


Dementia comes to have a major impact on a person’s basic activities of daily living, such as preparing food, looking after the home, personal hygiene, and going to the toilet. This often means that they eventually become dependent on others to support them in these activities. Some may be able to get support from friends or relatives in their home, or from a paid carer who comes in to see them. But for many, the level of dependency means they have to move into residential care. In fact, in the UK around one in three people with dementia live in care homes.

Financial problems

Dementia usually affects people after retirement age. But if someone gets early-onset dementia, it may affect their ability to carry on with their work. This can obviously lead to financial problems if they have to leave their job.

Someone who cares full-time for a relative or friend with dementia will probably have to give up their job as well, leading to even more financial problems. Around two-thirds of the total financial cost of dementia is paid by people with dementia and their loved ones.

Carer wellbeing

Caring for a person with dementia can cause significant changes in someone’s life, potentially affecting employment, education and social life, among other things. Ultimately, it can have a serious impact on the carer’s physical and mental health.

Can someone 'live well' with dementia?

Because dementia is progressive and can affect someone’s daily life profoundly, it’s easy to think that it’s not possible to live well with the condition. People can be very scared by the condition, and view it as a ‘death sentence’.

It’s true that living with dementia can be challenging and frustrating. But it’s important to remember that there are ways to help a person to live well with dementia. As with any illnesses that affect the brain and cognition, the difficulties that someone faces are not just to do with the physical changes in the brain. You also have to take into account the person’s environment. This includes their physical surroundings, relationships, and the way people communicate with them, among other things.

The person with dementia – and those around them – can adjust this environment to take account of the condition. This may make the experience of living with dementia considerably less challenging. This might include some of the following steps:

  • Communication – There are ways you can speak and communicate with a person with dementia, which help them to understand you.
  • Staying active – Staying physically and mentally active, and engaged in meaningful leisure or social activities, can have great benefits for a person with dementia.
  • Coping strategies – Even simple steps like making lists, labels and reminders can lessen the impact of memory loss.
  • The physical environment – For example, having a home that’s free from trip or slip hazards, and has grab rails installed. There are also ways to design the physical environment to help people with visual problems or hallucinations.
  • The community – Communities that are ‘dementia-friendly’ and inclusive enable people with the condition to participate confidently in public life. This can help to keep them active and independent, and reduce isolation.

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  • Produced by Nick Ridgman, Lead Health Editor, Bupa Health Content Team, November 2016
    Expert reviewer Professor Graham Stokes, Bupa Global Director of Dementia Care
    Next review due November 2019

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