About dementia

What is dementia?

Dementia is not an inevitable part of ageing and is not a disease in its own right. It is an umbrella term. It describes the symptoms that occur when the brain is affected by certain diseases or conditions which cause the gradual death of brain cells. This leads to progressive cognitive decline.

How fast cognitive decline progresses will vary from person to person and may depend on which type of dementia they have. Symptoms include loss of memory, changes in behaviour and mood, and problems with communication and reasoning skills.

This Alzheimer’s Society video explains what dementia is, how it affects the brain and how it might affect a person with the disease.

There are many different types of dementia. The most common are:

For more information on the above, see Early signs of dementia

Experiencing dementia from the inside

View the full video

Who does dementia affect?

More than 800,000 people in the UK are living with dementia – a number expected to rise to a million by 2021 (Alzheimer’s Society 2015).

The vast majority of people with dementia are aged 65 and over, but an estimated 40,000 people under 65 are living with dementia in the UK (Alzheimer’s Society 2015).

Figures published by the Alzheimer’s Society, Alzheimer’s Research UK and WHO show that:

  • Two thirds of people with dementia are women.
  • There are over 25,000 people with dementia from black and minority ethnic groups in the UK.
  • 225,000 will develop dementia this year; that’s one every three minutes.
  • Only 59 per cent of people with dementia in England have a formal diagnosis.
  • Worldwide, more than 47.4 million people are currently estimated to have dementia and 4.6 million new cases are diagnosed each year.
  • Dementia has a bigger impact on women – half a million women in the UK are now living with dementia. The condition is the leading cause of death in women in the UK.

The total estimated worldwide cost of dementia was US$604 billion in 2010. If dementia care were a country, it would be the world’s 18th largest economy, ranking between Turkey and Indonesia. If dementia care were a company, it would be the world’s largest by annual revenue exceeding Wal-Mart (US$414 billion) and Exxon Mobil (US$311 billion).

Alzheimer’s Disease International (2010) World Alzheimer report 2010: The global economic impact of dementia

Key statistics

Dementia costs the UK economy about £24 billion a year – more than cancer and heart disease combined (ARUK 2015).

The Alzheimer’s Society says that:

Figures published in January 2013 by the Alzheimer’s Society show that while there has been an increase in the number of people diagnosed with dementia, more than 400,000 people in the UK are living with dementia without knowing it.

What is being done to help people with dementia?

Since 2009, dementia strategies have been produced for England, Wales, Scotland and Northern Ireland with one central objective – to provide better care and support for people with dementia and their families.

The appointment of dementia advisers, the setting up of memory clinics to spot and treat the early signs of dementia and providing improved support for carers are among the many initiatives that have been launched in different parts of the UK.

In 2012, Prime Minister David Cameron launched a Challenge on dementia to ensure that England ‘is the best country in the world for dementia care and support and for people with dementia, their carers and families to live and is the best place in the world to undertake research into dementia and other neurodegenerative diseases’.

The Department of Health maintains a website for the Dementia Challenge, a good place to check on progress with implementation.