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Early diagnosis of dementia means early access to support, information and possibly medicines.

Early diagnosis of dementia means early access to support, information and possibly medicines.
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Dementia – an overview

2-minute read

Dementia is a condition that affects a person’s thinking, their behaviour and their ability to perform everyday tasks.

Over a period of months or years, most people with dementia may gradually:

  • lose their memory — at first for recent events, and later for events further back in their lives
  • have a personality change
  • lose interest in life
  • withdraw from their usual activities
  • lose their ability to care for themselves and for others around them

Dementia is an umbrella term that describes a collection of symptoms, not one specific disease.

There are more than 100 diseases that may cause dementia. The most common and well known is Alzheimer’s disease. Other forms of dementia include Lewy body disease, vascular dementia, younger onset dementia and frontotemporal dementia.

Dementia is more common in older people, although it can develop in people in their 40s or 50s. Dementia is not a normal part of ageing — most older people do not have dementia.

If you notice signs or symptoms of what may be dementia in yourself, or in a family member or friend, then it’s important to see a doctor.

If you or your family member or friend is diagnosed with dementia, then early diagnosis means early access to support, information and possibly medicines.

Also, there are other conditions, which may be treatable, that produce similar signs and symptoms to dementia. Delaying seeing a doctor may delay effective treatment.

Most cases of dementia are not inherited, although it depends on the cause. If you are worried about your risk of inheriting dementia, you can talk to your doctor or call Dementia Australia on 1800 100 500 and speak to a counsellor.

Expert advice - what is dementia?

Dementia gradually gets worse over time and is more common in older people. Learn more from an expert about how to recognise dementia.


Read the related video transcript

Last reviewed: October 2018

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Dementia Australia | What is dementia?

Information The information in this section defines dementia, describes the symptoms and causes of dementia and explains the difference between normal memory problems and dementia. What is dementia? Dementia describes a collection of symptoms that are caused by disorders affecting the brain. It is not one specific disease. Dementia affects thinking, behaviour and the ability to perform everyday tasks. Brain function is affected enough to interfere with the persons normal social or working life.

Read more on Dementia Australia website

Dementia Australia | About dementia

Information The information in this section defines dementia, describes the symptoms and causes of dementia and explains the difference between normal memory problems and dementia. What is dementia? What is younger onset dementia? Types of dementia

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Dementia Australia | Resources for Aboriginal and Torres Strait Islander communities

Help Sheets A series of help sheets about various dementia topics have been developed to inform Aboriginal and Torres Strait Islander people about dementia. What is dementia? Diagnosing dementia

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Dementia Australia | Resources for Aboriginal and Torres Strait Islander communities

Help Sheets A series of help sheets about various dementia topics have been developed to inform Aboriginal and Torres Strait Islander people about dementia. What is dementia? Diagnosing dementia

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Dementia Australia | Causes of dementia

*/ There is still much to learn about what causes dementia. There are many different types of dementia and the cause varies with type. The information below provides details of some of the major research areas.

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Dementia Australia | What is younger onset dementia?

What is younger onset dementia? Dementia is the term used to describe the symptoms of a large group of illnesses which cause a progressive decline in a persons mental functioning. It is a broad term which describes symptoms such as loss of memory, intellect, rationality, social skills and normal emotional reactions. The term younger onset dementia isused to describe any form of dementia diagnosed in people under the age of 65.

Read more on Dementia Australia website

Dementia Australia | What is younger onset dementia?

What is younger onset dementia? Dementia is the term used to describe the symptoms of a large group of illnesses which cause a progressive decline in a persons mental functioning. It is a broad term which describes symptoms such as loss of memory, intellect, rationality, social skills and normal emotional reactions. The term younger onset dementia isused to describe any form of dementia diagnosed in people under the age of 65.

Read more on Dementia Australia website

Dementia Australia | HIV associated dementia

What isHIV associated dementia? When someone has the human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) they may develop a complication to the disease which is known asHIV associated dementia, or as AIDS Dementia Complex (ADC).

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Dementia Australia | Vascular dementia

Vascular dementia is the second most common cause of dementia after Alzheimer's disease. What is vascular dementia? Vascular dementia is the broad term for dementia associated with problems of circulation of blood to the brain. Are there different types of vascular dementia? There are a number of different types of Vascular dementia. Two of the most common are Multi-infarct dementia and Binswanger's disease.

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Dementia Australia | HIV associated dementia

What isHIV associated dementia? When someone has the human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) they may develop a complication to the disease which is known asHIV associated dementia, or as AIDS Dementia Complex (ADC).

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