Understanding Alzheimer’s disease

7 May 2019
By Stephen Wiblin, Head of Clinical Strategy and Development


DementiaIn our previous Topicks article Forget me not… we debunked the common misconception that dementia and Alzheimer’s are one and the same, and clarified that dementia is used as a general term for a decline in mental ability which is severe enough to interfere with daily life.

Now we have established dementia as the umbrella term for a number of conditions which see a decline in brain function, over the coming months we will begin to explain the more common types of dementia, starting with Alzheimer’s disease.

According to NeuRA, Alzheimer’s disease is the most common type of dementia, accounting for 60 to 80 per cent of cases, meaning it affects one in 15 people over 65 years, and almost one in four people over 85 years.

Currently, researchers are not aware of what causes Alzheimer’s disease; they do, however, know that those with Alzheimer’s have abnormal material built up in their brain. This build up damages the brain, resulting in impaired memory, thinking and behaviour.

Types of Alzheimer’s

There are two different types of Alzheimer’s: sporadic and familial.

This is the most common form of Alzheimer’s, and while sporadic Alzheimer’s can affect anyone over 18, it is predominantly seen in people 65 years and older. Researchers are still unclear as to how or why Sporadic Alzheimer’s develops.

Familial Alzheimer’s is extremely rare, and ordinarily appears in those aged in their 40s or 50s. This is caused by a genetic condition which sees a mutation of one of several genes known to cause Alzheimer’s to develop. These genes influence the production of specific proteins in the brain, which in cases of Familial Alzheimer’s see these proteins clump together, creating large masses in the brain.

How does Alzheimer’s affect the brain?

A healthy brain works efficiently through neurotransmitters being passed from one brain cell to another, effectively sending messages throughout the brain from one cell to another.

Studies have shown the brain function of someone with Alzheimer’s suffers a breakdown in these messages being sent, meaning the normal nourishment and energy for the brain cell is not received, this leads to what were once healthy brain cells, dying of starvation.

Once these cells die, the brain then shrinks to fill the void left behind. For an individual with Alzheimer’s the rate of this progression varies from person to person.

The outer part of the brain is usually the first targeted by the disease. From here it progresses to deeper parts of the brain creating irreparable damage as it goes.

Symptoms of Alzheimer’s

Due to the death of cells and subsequent shrinking of the brain, short-term memory loss is one of the first symptoms of Alzheimer’s.

When the disease progresses deeper, it typically sees the individual lose long-term memory along with many of the brain’s other functions which predominantly affect behaviours. Dementia Australia identifies the common symptoms which include:


Unfortunately, as is the case with all dementia diseases, there is no test for Alzheimer’s. A diagnosis is made by performing a plethora of other tests to eliminate other potential illnesses and diseases. Effectively, diagnosing Alzheimer’s is a process of elimination.

Dementia Australia reports after eliminating other causes, a clinical diagnosis can be made with about 80-90 per cent accuracy.

Treatment and care

While there is currently no cure for Alzheimer’s, there is an array of treatments available to help patients relieve their individual symptoms. When patients are in care, a treatment plan will be developed by the individual’s doctor, in consultation with the patient, their family and administering carers to assist in slowing the cognitive impairment and help relieve secondary symptoms such as insomnia and depression.

There are some good resources available online at NeuRA and Dementia Australia.


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