What is dementia?

Dementia is an umbrella term used to describe a group of conditions that change and damage our brains. Dementia can happen to anyone, but as people get older the chances of developing dementia increase.

The symptoms each person experiences depends on the parts of the brain that are damaged. However, the most common dementia symptoms include changes in memory, thinking, behaviour, personality and emotions that affect a person’s ability to perform everyday tasks and interfere with their everyday lives.

Dementia is progressive, which means that damage will gradually spread through the brain and lead to their symptoms getting worse. Dementia is different for everyone – what they experience, how quickly they are affected is unique to them. And what they can do, remember and understand may change from day to day.

What are the warning signs?

The early signs and symptoms of dementia can be subtle and hard to recognise. Many conditions, such as stroke, depression, infections and normal ageing, can cause dementia-like symptoms, so it’s important not to assume its dementia.

If you think you or someone you know is showing signs of dementia, it's very important to see a doctor as soon as you have any concerns. This means that if the symptoms are the result of a treatable condition, you or they will get the right diagnosis and treatment early. If the symptoms are a result of dementia, an early diagnosis means you or the person with dementia and their family/whānau have early access to support, information, education and any appropriate medication. There is also time to plan for the future.

Click here to find out more about the warning signs of dementia.

What causes dementia?

There are many different diseases that cause dementia and, in most cases, there’s no known reason why they develop.

Some of the most common forms of dementia are:

  •  Alzheimer’s disease: This is the most common form of dementia, accounting for around two-thirds of cases. It’s caused by two abnormalities in the brain that stop communication between nerve cells, and this causes the cells to die.
  • Vascular dementia: This is the second most common form of dementia. It is caused by vascular disease in the brain’s blood vessels, which is caused by a single stroke or by several mini-strokes. Vascular dementia symptoms can begin suddenly after a stroke or gradually as disease in the blood vessels worsen. Some people will have both vascular dementia and Alzheimer’s disease.
  • Lewy Body disease: This disease is characterised by the presence of ‘Lewy Bodies’, which are abnormal clumps of protein in the brain nerve cells. These cause changes in movement, thinking, behaviour and attention spans. People with Lewy Body disease can go from almost normal performance to severe confusion within short periods, and may also hallucinate.
  • Frontotemporal dementia: This involves progressive damage to the brain’s frontal and/or temporal lobes, with symptoms often beginning when people are between 50 and 60 years old, or sometimes younger. Because of the areas of the brain this disease affects, people with this condition can often do socially inappropriate things, stop carrying out their normal responsibilities at work and home, be compulsive, repetitive, aggressive, show a lack of inhibition or they might act impulsively. They may also have difficulties with language.

For further information please go to our resource centre.




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