Common types of dementia

Dementia is the ‘umbrella’ term for a group of diseases which affect the brain.

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While there are many different types of dementia, Alzheimer’s disease and vascular dementia are the most common. Other common types include Fronto-temporal dementia, Lewy body dementia and mixed Alzheimer’s and vascular dementia. For each type of dementia, there can be different symptoms, treatments and management strategies.

Regardless of the type of dementia, there are benefits to getting a timely diagnosis, so if you notice any of the signs and symptoms of dementia in yourself or others, ask a GP for an assessment.

Alzheimer’s disease

Alzheimer’s disease is the most common type of dementia. About 50-70% of all people with dementia have Alzheimer’s disease. People with this type of dementia typically have trouble with short-term memory and this is usually affected more than their long-term memory of the past. People with Alzheimer’s disease may find it harder to concentrate, solve complex problems, or find themselves thinking more slowly.

We don’t know what causes Alzheimer’s disease, however there are medications and cognitive therapies that may slow progression of symptoms. Making positive changes including exercise, diet and staying mentally active can also help.

Read more about Alzheimer’s disease at Dementia Australia.

Vascular dementia

Vascular dementia is another common form of dementia. It’s caused by poor blood flow in the brain which can lead to brain cells dying, mini-strokes or larger strokes. People with vascular dementia experience problems with thinking depending on where the damage occurs in the brain.

People with vascular dementia may have heart disease or risk factors for heart disease, such as high cholesterol and high blood pressure. Managing these risk factors can help slow the progression of vascular dementia. Ask your doctor and read Reduce your risk.

Read more about Vascular Dementia at Dementia Australia.

Lewy Body Dementia

Lewy body dementia is a less common type of dementia. People with Lewy body dementia have trouble with their visuo-spatial skills, – that is understanding what they see and the spatial relationships of things around them – their concentration and attention, movement and falls. They frequently have abnormal movements during sleep. Their concentration and attention can fluctuate so that the person can be really clear in the morning but muddled and confused later that same day. These fluctuations can also be experienced over a few days. Their walking might become slow or stiff. People with Lewy body dementia sometimes see things that aren’t there (visual hallucinations) and may believe things that aren’t true (delusions). People with Lewy body dementia can benefit from physiotherapy and exercise physiology to help improve movement.

We don’t know what causes Lewy body dementia. Because of the similarities in symptoms, we think that Lewy body dementia and Parkinson’s disease are related diseases. However, in Lewy body dementia the difficulties with thinking are more prominent first, whereas in Parkinson’s disease the difficulties in movement are more prominent.

Read more about Lewy Body Dementia at Dementia Australia.

Fronto-temporal dementia

Fronto-temporal dementia is a less common type of dementia. People with fronto-temporal dementia have damage in the frontal and temporal lobes (regions) of their brains. People with fronto-temporal dementia often have symptoms that are different from other dementias. For this reason, clinicians may take longer to recognise, diagnose and treat this type of dementia. People with fronto-temporal dementia often have to educate others (including health professionals) about fronto-temporal dementia.

There are three subtypes of fronto-temporal dementia, each with a different pattern of symptoms.

Semantic variant of primary progressive aphasia is a subtype of fronto-temporal dementia where the person starts to lose the meanings of words. People with semantic dementia have trouble expressing themselves with words, understanding language, reading and writing. They may benefit from speech therapy with experts in improving communication.

Progressive non-fluent aphasia is a subtype where the person has difficulty speaking fluently. People with progressive, non-fluent aphasia have trouble expressing themselves and following conversations. They may benefit from speech therapy with experts in improving communication.

Behavioural-variant frontal dementia is a subtype where the person’s behaviour, mood or personality changes. People with behavioural-variant frontal dementia may become apathetic, socially disinhibited or socially unaware. They often have trouble with judgement, making decisions or problem solving. They might develop new habits that they do repeatedly, including eating and drinking different foods or drinks.

Read more about FrontoTemporal Dementia at Dementia Australia. The Sydney University Frontier Clinic specialises in Fronto-Temporal Dementia.

Mixed dementia

People with mixed dementia have a combination of brain diseases, often Alzheimer’s disease and vascular brain changes. People with mixed dementia have a mixture of symptoms depending on the combination of brain diseases.

Read more about Mixed Dementia at Alzheimer’s Society Calvary.