Alzheimer’s disease is a progressive neurological condition which causes changes to the way a person thinks and functions over time. It is characterised by problems in thinking, learning, memory and judgment (Kraus, 2017). The accumulation of amyloid beta plaques and the formation of neurofibrillary tangles along with reduced acetylcholine (a chemical messenger which assists transmission of information from neuron to neuron) are considered to play a significant role in Alzheimer’s disease. Over time, brain cells die, the brain atrophies (degenerates) and the person requires assistance to live independently.
What is the difference between Alzheimer’s disease and dementia?
We often hear the terms Alzheimer’s disease and dementia used interchangeably. The term dementia is a syndrome or a collection of symptoms which suggests the presence of a disease or diseases. Those symptoms may be caused by Alzheimer’s disease or they may be caused by over 150 other diseases known to affect the brain, resulting in similar symptoms. Just because a person is ageing does not mean they will develop dementia. Although more common in older Australians, dementia isn’t a normal part of the ageing process.
In short, every person with Alzheimer’s disease has dementia, but not everyone with dementia has Alzheimer’s disease.
What are the symptoms of Alzheimer’s disease?
Early symptoms include short term memory loss, episodes of confusion or disorientation and changes in language (for example remembering the names of common objects). As Alzheimer’s disease progresses, more parts of the brain are affected and symptoms become more complex. These may include:
- Apraxia: The inability for the person to make purposeful movements despite having the muscle strength and will to do so. Examples may include difficulties dressing, difficulties manoeuvring themselves to sit in a chair and in later stages, basic functions like chewing and swallowing may be impacted.
- Aphasia: This describes a range of difficulties with communicating including a loss of ability to understand common words, difficulty getting a message across and misunderstanding of what is being said by others. The person may ask you to repeat yourself or say they can’t hear you when the issue is not hearing but processing what is being said. As a method of coping with these changes, the person may reply to questions or requests with statements like ‘I don’t care’ or ‘you choose’ rather than making a decision, expressing an opinion or answering a question they may not have understood.
- Anomia: Another communication difficulty, anomia is the inability to remember the correct word. The person may know what they want and what it is used for, but cannot remember the correct name. For example, whilst preparing to get himself a cup of tea, Barry asks his wife where the scoops are kept. His wife looks puzzled until Barry explains he needs the scoop for the sugar. Barry’s wife directs him to the cutlery draw where he locates the object he needs. A teaspoon.
- Agnosia: People experiencing agnosia have difficulty identifying familiar objects and/or people. Although their eyesight is fine, they cease to recognise an item or person despite previously knowing what it was or who they were. This can affect a person’s ability to achieve everyday tasks. For example if a person no longer recognises a toothbrush, they will not know what to do with it and therefore, will not brush their teeth. Agnosia can be distressing for families if their loved one with dementia ceases to recognise them in the later stages of the disease.
- Amnesia: Early in Alzheimer’s disease amnesia commonly presents as short-term memory loss. The person may have difficulty remembering where they parked their car, forget appointments or repeat things they’ve already said. As Alzheimer’s disease progresses, forgetfulness can begin to interfere with the person’s ability to function day to day. They may forget the way to previously frequented destinations (such as a relative’s home or the local supermarket) and become disorientated. They may have difficulties tracking finances, remembering medications or have no recollection of appointments they’ve made even when reminded. Amnesia can also cause the person to lose insight. They can forget that they’re forgetful. In these instances, people with Alzheimer’s disease will believe they are functioning independently even though they’re receiving significant support.
Does Alzheimer’s disease have stages?
Every person with Alzheimer’s disease experiences it differently. They may experience different symptoms at different times throughout the illness. Sometimes it has a slow progression and sometimes the onset and progression is quite rapid. There are also other factors which can have an impact such as the person’s life experiences, their overall mental and/or physical health as well as access to medical and psychosocial care and support. For these reasons there are no clear stages or reliable patterns of symptoms.
How is Alzheimer’s disease diagnosed?
Alzheimer’s disease is the most commonly diagnosed form of dementia in Australia, accounting for up to two thirds of diagnosed cases of dementia. A GP is the best place to start on the path to diagnosis. Because there are so many other conditions that can look very similar to Alzheimer’s disease (such as delirium, depression, vitamin and mineral deficiency and thyroid dysfunction to name a few) the doctor will begin by taking a case history. He or she will record all the symptoms currently experienced. If the person lacks insight into their deficits, a care person may also be required to provide input regarding the changes the person is experiencing.
The GP may refer on to a neurologist or geriatrician where the person will undergo further tests including brain imaging, memory tests and various pathology reports to rule out any other possible reasons for the symptoms.
Scans may or may not identify changes in the brain in the early stages so it often takes some time and repeated visits to doctors and specialists to eliminate all other options and gain a dementia diagnosis.
There is no one test that can be done to diagnose Alzheimer’s disease. Doctors will look for key markers in the disease such as a family history, changes to the temporal lobes, common early symptoms such as short term memory loss and memory test scores to guide their diagnosis.
What are the treatment options available for Alzheimer’s disease?
There is no cure for Alzheimer’s disease but a range of treatments are available to help relieve some of the associated symptoms. They are approved for treatment of dementia but are not effective for everyone.
Cholinesterase inhibitors such as Aricept and Donezepil work by preventing a substance called acetylcholine from being destroyed. Acetylcholine is important for neurotransmission. This medication is most effective in the early to moderate stage of dementia.
Ebixa and Memanta are N-methyl-D-aspartate (NMDA) receptor antagonists. They work by blocking glutamate, a neurotransmitter found in high proportions in people with Alzheimer’s disease. This treatment is most commonly used in the later stages of dementia.
There are also a range of medications used to treat associated conditions which occur commonly in conjunction with dementia. Medications to treat depression, anxiety, sleep disturbances and to assist in the management of psychiatric symptoms such as hallucinations and delusions may also be prescribed.
Who is likely to develop dementia?
Alzheimer’s disease can be genetic but most cases are sporadic meaning there is no known family history of the disease.
Alzheimer’s disease does not discriminate and anyone can develop dementia.