Introduction

When faced with an initial diagnosis, it can sometimes be difficult to come to terms with. Yet, with time, most people can accept their diagnosis and move forward to discuss potential treatment plans. 

In some cases, however, individuals show what is perceived as long-lasting denial, or complete rejection of a diagnosis. This is known as anosognosia, a neurological disorder in which an individual has a lack of self-awareness towards their illness.¹ Whilst anosognosia can be seen in response to some physical conditions, it is mainly associated with neurodegenerative disorders, such as Alzheimer’s disease (AD).²

Under the umbrella term of dementia, AD can be defined as a progressive condition that typically results in memory loss and altered behaviour. These symptoms directly result from the gradual build-up of toxic proteins within the brain, caused by the reduced efficiency of clearance pathways.

It is currently thought that up to 80% of people with AD are affected by anosognosia.^{3, 4} Despite this high prevalence, anosognosia is a symptom that is often left underestimated in its effect on both the individual diagnosed with AD, and their caregivers. By highlighting the key signs of anosognosia in AD, this article aims to provide insight into this symptom that frequently goes under the radar. 

Characteristics and causes 

Characteristics 

Anosognosia in AD is characterised by the following:

• Lack of self-awareness regarding AD diagnosis that worsens as the disease progresses
• Denial and/or downplaying the severity of the diagnosis 
• Anger towards caregivers and doctors who are aware of the diagnosis
• Refusal of treatment 

It is important to note that each individual who has anosognosia alongside their AD diagnosis will experience the symptoms to a different degree. Some individuals may be unaware of one area of their disease, whilst being able to understand another. It is also common for patients to inconsistently admit their symptoms.¹ For example, one day an individual might reveal they are having problems with their memory, and then the next day they are adamant that they can remember perfectly well

Causes 

Since the nature of AD is neurodegenerative, it is thought that the disruption of connections in the brain affects its ability to recognise problems. The two main regions of the brain that, when damaged, are associated with anosognosia are the frontal lobe and the hippocampus.^{5, 6}

Damage to the frontal lobe 

In a healthy individual, this area at the front of the brain is largely responsible for organising new information and providing logic and reasoning to keep an updated self-image. 

In AD patients, toxic proteins build up into bundles that are known as ‘amyloid plaques’.⁷ Over time, these clumps can disrupt the function of certain regions of the brain, like the frontal lobe. Reduced function in the frontal lobe manifests as reduced self-awareness, as you are unable to keep up to date with new information.⁸

Damage to the hippocampus 

The hippocampus is also known as the memory centre of the brain. In healthy individuals, its main function is to hold onto short-term memories and send them off to long-term storage if necessary. 

Damage to the hippocampus seen in AD results in memory loss, as well as individuals not being able to form new memories.⁷ This can trigger the onset of anosognosia due to the close link between new memory formation and keeping an updated sense of self.

Assessment and diagnosis

There are 3 main methods that are currently used to assess anosognosia in patients with AD:

• Clinical Insight Rating Scale (CIRS) 
• Anosognosia Questionnaire-Dementia (AQ-D)
• Self Appraisal Discrepancies (SADs) 

Clinical insight rating scale (CIRS)

CIRS is a process in which a doctor interviews the patient and the caregiver separately to assess the level of awareness of the disease, making note of full (0), partial (1) or non-insight (2) to the questions. If the final score is 2 or above, patients are considered to be anosognosic.⁹

Anosognosia questionnaire dementia (AQ-D)

This assessment is divided into cognitive and behavioural sections. The cognitive section assesses the patient's function regarding daily activities, whilst the behavioural section covers mood changes. Both the patient and the caregiver answer the questions on form A and form B respectively. The total AQ-D score is given based on the difference between form B and form A.¹⁰

This assessment is designed to assess the differences between the patient and the caregiver, regarding self-awareness of their diagnosis. A higher score indicates reduced awareness, with the caregiver rating the patients as more impaired than the patients believed themselves to be. 

Self-appraisal discrepancies (SADs) 

This technique relies on the patient rating their perception of their performance of a task, which is later compared to how well they actually performed.¹¹ After the comparison between the scores has been made, patients are given a SAD score, with overestimations of their performance often suggesting the presence of anosognosia.

A commonly used technique used to create SAD scores is the Stroop test.^{12, 13} This technique involves giving the patient a list of colour words printed in different colours and having the patient read off the ink colour, whilst ignoring the word itself. For example, RED, BLUE, YELLOW, PINK, GREEN. This process is timed to measure the speed at which patients can process information in the presence of other distractions. 

Management and treatment

Challenges 

The onset of anosognosia in AD is directly related to the degeneration of the brain, therefore there is no treatment available. In addition to this, symptoms tend to worsen as the disease progresses. This can have a negative impact on people caring for individuals diagnosed with both anosognosia and AD. 

Despite this, there are several options available that could help individuals and caregivers manage the symptoms of anosognosia. 

Vestibular system stimulation 

The vestibular system is responsible for taking in our surroundings and combining sensory information to allow individuals to stand upright and maintain balance.¹⁴  Whilst this may seem unrelated to the symptoms of anosognosia, stimulating this system with electrodes placed behind the ears has proven to be a temporary fix for improving an individual's awareness of their surroundings and enhancing processing.¹⁵

Cognitive therapy

Talking therapy is a potential long-term process that can aid in the management of anosognosia in those with AD. Whilst no evidence suggests cognitive therapy will cure anosognosia in AD, having regular sessions with a therapist may help the patient increase their awareness of their condition to manage the symptoms.

Summary 

Anosognosia can be confusing for individuals with the condition, and frustrating for caregivers. Whilst it may come across as stubbornness, anosognosia affects an individual's ability to understand what is happening within their own body. This is why it is vital to be patient with those who have anosognosia and AD and to provide a strong support system with the hope of building a trusting environment. When surrounded by positivity, individuals are more likely to engage in treatment which will help manage their symptoms. 

FAQs

Do people with alzheimer’s always have anosognosia?

Not everyone with Alzheimer’s disease has anosognosia, however the prevalence rate is high. It is believed that up to 80% of people with the disease have anosognosia. 

What is the difference between anosognosia and denial?

Denial is a process in which you are able to take in information but minimise or dismiss the facts in order to feel safe. Anosognosia occurs as a result of brain damage or degeneration that causes structural changes in your brain, meaning you cannot process the information correctly. 

How to support someone with both alzheimer’s disease and anosognosia? 

Try to remain positive and connect with the emotions of loved ones who are diagnosed with Alzheimer’s disease and anosognosia. If possible, aim to provide a schedule with daily tasks, as it reduces the need for the individual to rely on their memory.