What is Alzheimer’s disease?

What are the stages of Alzheimer’s disease?

The 7 Stages of Alzheimer’s disease, also known as the Global Deterioration Scale (GDS), was developed by Dr Barry Reisberg, Director of the Fisher Alzheimer’s Disease Education and Research Program at NYU Grossman School of Medicine.

The guideline is used by professionals and caregivers around the world to identify what stage of the disease a person is in and demonstrates how Alzheimer's disease progresses.

In summary, Stages 1-3 are the pre-dementia stages; Stages 4-7 are the dementia stages; and Stage 5 is the point where a person can no longer live without assistance.

Here are the 7 stages of Alzheimer's disease broken down in more detail:

Stage 1: No dementia is seen

There are generally no dementia symptoms at this stage, but there may be early monitoring based on family history.

Stage 2: Subjective memory loss

The earliest symptoms appear, such as forgetfulness. This may include forgetting people’s names or having trouble recalling where they have recently placed things.

Stage 3: Mild cognitive impairment

Mild cognitive impairments become noticeable often by someone very close to this person. These impairments can include reduced memory and concentration.

Stage 4: Moderate cognitive decline (mild dementia)

Alzheimer’s disease is often diagnosed with considerable accuracy at this stage. Memory loss and the inability to perform everyday tasks is more evident. This can include the inability to pay rent or other bills, the inability to shop for groceries or difficulty ordering from a menu in a restaurant. Despite these symptoms of moderate Alzheimer's disease, a person at this stage can still potentially live independently in community settings.

Stage 5: Moderately severe cognitive decline (moderate dementia)

Moderate to severe symptoms have reached the stage where help is required from loved ones or caregivers.

Stage 6: Severe cognitive decline (moderately severe dementia)

At this stage, the person may need help with very basic tasks such as eating, bathing and putting on clothes.

Stage 7: Very severe cognitive decline (severe dementia)

This is the most severe and final stage of Alzheimer’s disease, also known as advanced Alzheimer's disease, and may include a loss of speech and facial expressions.

The rate of progression throughout each stage varies from person to person. Usually, Alzheimer’s disease leads to complete dependence on a caregiver and finally death – usually from another contributing illness such as pneumonia. A person may live from three to 20 years with Alzheimer’s disease, with the average lifespan being seven to ten years.

How is Alzheimer’s disease diagnosed?

There is currently no single test to diagnose Alzheimer’s disease. However, there are several ways a clinical diagnosis can be made. These include:

• Detailed medical history
• Thorough physical and neurological examinations
• Test of intellectual function
• Psychiatric assessment
• Neuropsychological tests
• Blood and urine tests
• Lumbar puncture for cerebral spinal fluid tests
• Medical imaging, such as brain scans (MRI, PET).

According to Dementia Australia, these tests are typically used to help eliminate other conditions with similar symptoms.

A brain scan, such as an MRI (Magnetic Resonance Imaging) for example, can detect loss of brain cells, which indicates the disease's progress.

After eliminating other causes, a clinical diagnosis of Alzheimer’s disease can made with about 80-to-90-per-cent accuracy.

What treatment is available?

At present, there is no cure for Alzheimer’s disease. So, how is Alzheimer's disease treated? Treatment is aimed at managing and alleviating the symptoms (like behavioural symptoms) associated with the condition.

Common treatments include:

• Medications – which are often used to treat behavioural symptoms associated with the disease and form part of a comprehensive treatment plan in consultation with a GP or health professional.
• Speech therapy – to help cope with a decline in language abilities. A speech therapist can also help you find alternative ways to communicate.
• Environmental changes – maintaining an environment that doesn’t agitate or upset someone is vital. People with behaviour problems are most comfortable in environments that are familiar, quiet, and away from large crowds. This means a drastic change in environments to something unfamiliar, noisy and busy can be very counter-productive.

Remember, only a medical practitioner such as a doctor or specialist can diagnose dementia, such as Alzheimer's disease. If an official diagnosis has been made, there is a lot of support available to help you and your loved ones manage. A good place to start is by visiting Dementia Australia’s website or by calling the National Dementia Helpline on 1800 100 500. They offer support, information, education and counselling. 

Did you know?

• Dementia is the term used to describe a number of neurological conditions that affect a person’s cognitive, behavioural, functional and physical ability.
• There are more than 100 different types of dementia, and each has its own causes.
• Alzheimer’s disease is the most common type of dementia and may contribute from 60 to 70 per cent of cases.
• Dementia is the second leading cause of death in Australia, according to the Australian Bureau of Statistics (2020).
• In 2021, there are an estimated 472,000 Australians living with dementia. Without a medical breakthrough, this number is expected to increase to 590,000 by 2028, and more than 1 million by 2058.
• The biggest risk factor for having Alzheimer’s disease is increasing age, with three in ten people over 85 having dementia.
• Almost 1.6 million Australians are involved in the care of someone living with dementia.
• People with dementia account for 52 per cent of all residents in residential aged care centres.
• Dementia affects almost 50 million people worldwide.
• Every three seconds, someone in the world develops dementia.