Dementia - what you need to know

Dementia describes a collection of symptoms caused by disorders affecting the brain.

Dementia is not a normal part of getting older, and it isn’t one specific disease. Instead, it’s a broad term that covers the effects on people of a number of different medical conditions.

Those conditions include Alzheimer’s disease, vascular dementia, frontotemporal dementia, the Lewy body dementias and more.

The effects of dementia vary from person to person, but generally, dementia affects your mood, memory, thinking and behaviour.

Dementia can happen to anybody, but it is much more common after the age of 65.

In 2025 there are an estimated 110,600 people in Victoria living with all forms of dementia. This figure is projected to increase to an estimated 216,400 by 2054 with a projected percentage change of 96%.

Dementia is now the leading cause of death for all Australians, according to the Australian Institute of Health and Welfare (AIHW).

There are things you can do to reduce your risk of developing dementia. Globally, 45% of all dementia diagnoses are preventable.

There’s currently no known cure for dementia, but there are treatments for many of the symptoms. Some people with dementia lead active and fulfilling lives for many years after their diagnosis.

Researchers around the world are working on new treatments for dementia.

Preventing dementia

Dementia is not inevitable: it isn’t a normal part of ageing. Globally, 45% of all dementia diagnoses are preventable.

All through your life, your brain is shaped by the way you live, learn, eat, sleep and move. These factors can influence your risk of developing dementia, and there are many things you can do to keep your brain healthy and reduce that risk.

There are 14 known modifiable risk factors for developing dementia. They are:

• education
• hearing loss
• LDL cholesterol
• depression
• traumatic brain injury
• physical inactivity
• diabetes
• smoking
• high blood pressure
• weight
• excessive alcohol
• social isolation
• air pollution
• untreated vision loss.

To find out more about each one, and what you can do to reduce your dementia risk, visit Risk factors for developing dementia.

Causes and types of dementia

Dementia can happen to anybody at any age, but it is much more common after the age of 65.

Many different conditions can cause dementia. For some people diagnosed with dementia, the exact cause is never known. It is also possible to have multiple conditions causing dementia symptoms.

Alzheimer’s disease is the most common type of dementia. Alzheimer’s disease is estimated to account for at least 60% of dementia diagnoses.

Other types of dementia include vascular dementia, frontotemporal dementia, dementia with Lewy bodies.

There are many conditions that can also lead to the symptoms of dementia. They include Parkinson’s disease, chronic traumatic encephalopathy (CTE), blast-induced brain injury, Down syndrome and human immunodeficiency virus (HIV).

For more information, see Causes and types of dementia.

Genetics, inheritance and dementia

Your genes play a role in how likely you are to develop some of the medical conditions that can lead to dementia. Genetic variations can make you more likely to develop some forms of Alzheimer’s disease and frontotemporal dementia, for example.

Genetics and Alzheimer’s disease

The most important known gene affecting your risk of developing Alzheimer’s disease is called Apolipoprotein E. It has three types: type 2, type 3 and type 4.

Every person has two Apolipoprotein genes. You can have two of the same type or two different types. If you have at least one type 4, known as ApoE ε4, and especially if you have two type 4s, you are at higher risk of developing Alzheimer’s disease than people with other types.

But the risk isn’t that much higher: half of all people aged 85 who have two copies of ApoE ε4 don’t have symptoms of Alzheimer’s disease.

ApoE ε4 has also been associated with increased risk for cardiovascular disease and vascular dementia.

One rare form of Alzheimer’s disease is passed from generation to generation: Familial Alzheimer’s disease (FAD).

There are three genes which everyone has, called:

• presenilin 1
• presenilin 2
• amyloid precursor protein gene (APP).

These genes are usually harmless. But they can mutate in a specific way that causes FAD.

If you have one of these mutated genes, you will eventually develop Alzheimer’s disease, usually in your 40s or 50s. Your biological children will have a fifty per cent chance of inheriting that gene. If they don’t inherit the mutated gene, they can’t pass any risk of FAD on to their children.

Familial Alzheimer’s disease is very rare. At any given time in Australia, no more than 100 people are likely to be affected by FAD.

Genetics and frontotemporal dementia

There is a rare form of frontotemporal dementia that is inherited through your genes. It’s called familial frontotemporal dementia.

Familial frontotemporal dementia makes up only about ten to fifteen per cent of frontotemporal dementia cases.

For more information, visit Dementia Australia’s Genetics and dementia page.

Genetics, Down syndrome and Alzheimer’s disease

The genetic variations that cause Down syndrome greatly increase your risk of developing Alzheimer’s disease.

If you have Down syndrome, you are more likely to develop Alzheimer’s disease, and at a younger age. People with Down syndrome make 1.5 times as much of a substance called amyloid precursor protein as other people. This seems to cause earlier Alzheimer’s disease symptoms in people with Down’s syndrome.

For more information, visit Dementia Australia’s Down syndrome and Alzheimer’s disease page.

Inherited forms of dementia are rare, but if there’s a history of dementia in your family, talk to your doctor.

Signs and symptoms of dementia

Because dementia can be caused by so many different conditions, everyone’s experience of dementia is unique. Symptoms of dementia can vary greatly from person to person and depend on the type of dementia you’re experiencing.

But broadly, dementia can affect your:

Memory

You might find it harder to remember recent events, names of things and people. It might also get harder to make new memories.

Thinking

You might get more confused, have trouble concentrating, planning and problem-solving, struggle to complete everyday tasks, find it hard to think of the right word or express yourself, and find it hard to judge distances, directions and time.

Mood

You might find yourself feeling less motivated and social, more prone to depression, anxiety, agitation and mood swings, or otherwise not yourself.

Behaviour

You might start saying or doing things that are out of character for you. You might become restless and wander, and have more disturbed sleep.

Movement

Some forms of dementia can affect your balance, walking, continence, speech and swallowing.

For more information, see Early warning signs of dementia and Causes and types of dementia.

Diagnosing dementia

If you or someone else has noticed signs that your memory, thinking, behaviour and mood are changing, it can be scary. It’s the same if you notice signs in someone close to you. What if it’s bad news? You might feel it’s better not to find out.

That’s a normal feeling. But it is definitely better to find out as early as you can, because:

• if it’s not anything serious, you can put your mind at rest
• if it’s some other condition than dementia, you may be able to start getting treatment
• if it’s a dementia diagnosis, the sooner you know, the more you can do.

Talk to your doctor

The first person to talk to about getting tests for changes in your memory, thinking, behaviour and mood is your doctor.

Your GP will listen and talk with you about any changes you or other people have noticed. They might ask:

• how strong these changes are
• if they come and go
• if they’re getting worse
• how often you have them
• when they started.

They might also ask you about your diet, whether you smoke or drink, and your medical history. If you’re completely open and honest with your answers, the doctor has the best chance to work out what’s happening.

Depending what they find, the doctor might recommend some more tests, or refer you to a medical specialist. That specialist might be a:

• neurologist: a doctor who specialises in the brain and nervous system
• geriatrician: a doctor who specialises in conditions affecting older people
• psychiatrist: a doctor who specialises in mental health.

Testing for dementia

There isn’t one single test that tells you if you have or don’t have dementia.

Instead, doctors will do several different kinds of test. The results of these tests will help them rule out some conditions, and get closer to working out what’s causing your changes.

That process can take time. Even after testing, your doctor may tell you it’s ‘possible’ or ‘probable’ that you have one or more conditions.

They might tell you to wait and take more tests in a few months or a year. They will compare the new results with the old to see what’s changed. This can help them make a more certain diagnosis.

Before you agree to any tests, it’s okay to ask questions. It’s your body and your health, and you are always in charge of the process. You can also change doctors at any time, or get a second opinion.

When your doctors recommend tests, they’re like detectives, looking for evidence to tell them what might be causing your changes. The tests they recommend might include:

Cognitive tests: these tests measure your thinking abilities, like memory, concentration, spatial awareness, problem solving, counting and language.

Lab tests: Blood, urine and other tests can help spot another condition that could explain your symptoms.

Brain scans: Brain scans, including x-rays, MRIs, CAT scans and PET scans, take highly detailed images of your brain. They help your doctors see what’s going on in your brain and look for causes of the changes you’re experiencing. Scanning your brain is usually painless and doesn’t involve any surgery.

Genetic tests: Genetic testing for dementia is rarely required, because genetic causes of dementia are rare.

Cerebrospinal fluid protein tests: Cerebrospinal fluid (CSF) is a clear fluid that cushions your brain and spinal cord, like the water around you in a bath. In some rare cases, this can be used to support a diagnosis of Alzheimer’s disease, but it’s not a common test.

For more information, visit Dementia Australia’s Testing and diagnosis of dementia page.

None of these tests on their own can say for sure if you do or don’t have dementia. But like pieces of a puzzle, your doctors can use them to put together a picture that suggests one diagnosis or another. If they think the evidence is strong enough, they may give you a diagnosis of dementia.

Getting a dementia diagnosis

Only a medical professional who has your test results can diagnose you. This usually means your GP or a specialist, often working together.

If your doctor diagnoses you with a form of dementia, there’s no wrong reaction to have.

Some people are relieved to know there’s a cause for what’s happening. But for many people, getting a diagnosis of dementia can be frightening.

It can also be a shock for families, friends and carers of someone getting a diagnosis of dementia.

When your doctor tells you the diagnosis, you might find it hard to take it all in. It’s sometimes hard to think of the questions you want to ask in the moment.

It’s okay to book another appointment with your doctor, to give you time to think of everything you need to ask or say.

The National Dementia Helpline is for you. You can call, email or webchat, any time, day or night. You can talk about the diagnosis, or any other aspect of dementia. No question is too small or too big.

The progression of dementia

Everyone experiences dementia differently, so the way your symptoms change will be unique to you. You might have better days and harder days.

But dementia is a progressive condition. That means that your symptoms will become more serious over time. That might happen quickly or over several years.

You can think of dementia as having three broad stages. These stages can overlap. They’re not exactly the same for everyone, and they may happen more slowly or quickly for different people.

Early-stage dementia

In mild or early-stage dementia, you might experience some changes in your thinking and memory.

You might sometimes repeat yourself, mix up words, or misplace things more than you used to.

You might struggle more in social situations, or feel less motivated.

But most people with early-stage dementia are able to support themselves. In fact, many people at this stage don’t have a diagnosis of dementia, because their changes haven’t felt worrying enough for them to get tested.

Middle-stage dementia

In moderate or middle-stage dementia, the changes to your mood, memory, thinking and behaviour are stronger. They have a bigger effect on your ability to do everyday things and take care of yourself.

You might have more trouble concentrating, understanding, reasoning and communicating.

You might forget how to dress or bathe, or to recognise family and friends.

You might experience confusion, distress, mood changes and aggression.

These stronger changes mean you will likely need support from other people, at home and in the community.

Late-stage dementia

In severe or late-stage dementia, your symptoms will be severe. You may be unable to communicate, walk, control your bodily functions or look after your hygiene. You may be unable to remember people or places, and be unable to form new memories.

At this stage, you will need constant supervision and care. You may need to live in an aged care facility, where you can get the professional care you will need.

Treatment and management of dementia

Right now, there’s no known cure for dementia.

However, there are treatments and support services help to ensure your best possible quality of life as you live with the condition. There are also new and promising treatments that have been shown to slow the progression of Alzheimer’s disease symptoms at different stages.

For more information, visit Dementia Australia’s Treatment and management of dementia page.

It is possible to stay safe, connected, healthy, active and supported with dementia. For more information, visit Dementia Australia’s Living with dementia page.

Dementia Australia support

When I was diagnosed with Alzheimer’s (disease) I had never been so scared in my life […] I am happy to say that I have received amazing support from my family, medical team and Dementia Australia.

- Linda, living with young onset Alzheimer’s disease

Whatever your experience of dementia, we're here for you. You can contact the National Dementia Helpline any time of the day or night for information, advice and support.

Where to get help (key organisations with web links and phone numbers):

• Your GP
• The National Dementia Helpline, 1800 100 500
• NDIS: the National Disability Insurance Scheme: available if you’re diagnosed with dementia when you’re under 65.
• My aged care: support in navigating decisions around aged care.
• Carer Gateway: emotional and practical services for carers.
• Dementia Behaviour Management Advisory Service (DBMAS): 24/7 advice for people caring for someone with dementia.