What is dementia? Guest blog by Dr Jane Pritchard – No. 2

Dr Jane Pritchard’s new fortnightly series about dementia, sharing advice and practical information for local families and carers.

What is dementia? Brain changes and common early symptoms

Before sharing hints and tips for caring for someone in later entries, I wanted to start with giving a background to dementia. Many people are confused about the difference between Alzheimer’s disease and dementia, and I want to distinguish the two and explain how the brain changes. Many families I see in Hammersmith & Chiswick also ask me about the first signs of dementia, so in today’s blog entry I will also be describing the first signs and symptoms to look out for.

Overview

Dementia is the name given to a range of degenerative conditions that affect the brain. There are thought to be currently over 982,000 people with dementia who live in the UK, and one in three of us will develop dementia in our lifetime, according to research by the Alzheimer’s Society.

Research by Hammersmith & Fulham Council in 2021 found that approximately 770 older people live with dementia in this borough, making up 3.5% of the resident population over 65 years of age. 36 people under 65 years, meanwhile, had a diagnosis of dementia, 4.5% of all recorded cases of the condition.

Compared to Hammersmith & Fulham, Hounslow (including Chiswick) has significantly more people diagnosed; over 2,300 people. Many more are thought to have dementia but remain undiagnosed. Across England, a third of people with dementia never receive an official diagnosis in their lifetime.

There are many different types of dementia, Alzheimer’s disease being the most well-known. Each has their own causes and symptoms, but it should be noted that this is a rough guide. There is often variation in signs between people with dementia, and they will move through different stages, so many of the symptoms won’t be present initially, but will begin to emerge over time.

The surrounding environment and the people around the person can also play a large role in the person’s experience. A future blog will look at the different stages of dementia and the journey of people and their families that results.

Common forms of dementia

Alzheimer’s disease

Alzheimer’s disease accounts for approximately 80% of dementia diagnoses. It is associated with the build-up of protein fragments called amyloid plaques, which are abnormal protein deposits in the brain and lead to brain shrinkage over time. Tau ‘tangles’ are also present in Alzheimer’s disease. Tau is a natural protein occurring in the brain which helps to maintain nerve cell structure. These become damaged and change form, creating clumps, or ‘tangles’.

There is also a reduction in some neurotransmitters, the chemical messengers that help nerve cells communicate with one another. Amyloid plaques often build up many years before symptoms begin. In most cases, Alzheimer’s disease is not usually hereditary, although a number of genes have been identified that can increase a person’s risk, especially where dementia is present at a younger age. Older age, however, remains the biggest risk factor.

One of the most well-known symptoms of Alzheimer’s disease, and often one of the first to appear, is memory loss. This usually affects short-term memory first, including memory for recent events. This is because the temporal lobe of the brain, where memories are stored, becomes damaged early in the condition. The person may begin to forget appointments, conversations or recent events, and may find it difficult to follow the plot of television programmes or films.

In the early stages, people with Alzheimer’s disease may also forget words, where they have put items, and sometimes conversations with others. Difficulties with reading, writing and understanding others will develop over time. There are practical steps that can support communication and memory, which will be discussed in future blogs.

Longer-term memory loss usually occurs later in the condition. At this stage, the person may no longer recognise their home or familiar faces and may experience what is called ‘time-shifting’, where they appear to be living in an earlier period of their life, sometimes even decades ago.

Alzheimer’s disease gradually progresses over several years and can affect all areas of day-to-day life, including carrying out tasks independently such as washing, dressing, going to the toilet and, eventually, walking and eating and drinking.

Changes in mood, anxiety levels, personality and behaviour are also common and may occur at any stage of the condition, although behavioural change is more likely to happen later on when the person struggles to communicate their needs and use this to express themselves.

This is where talking to an Admiral Nurse has particular value, in making sense of what is happening, and in helping families and carers to cope. I see many people with complex needs in Hammersmith & Chiswick, and distressed behaviour is the top reason why those around the person struggle. Resolving this behaviour takes patience and skill, as well as learning strategies, and meeting the person’s needs in other ways.

Vascular dementia

Vascular dementia is caused by changes in the brain’s blood supply, which affect how much oxygen and glucose reach brain cells. When brain cells do not receive enough of these, they can become damaged or die. The symptoms a person experiences depend on which areas of the brain are affected, as different areas control different functions.

Common symptoms, however, include reduced information-processing speed, language, memory and how the brain interprets information from the senses. Reduced ability to hear, for example, is common and there is now an established link between hearing loss and risk of developing dementia.

Lifestyle factors can contribute towards the risk of developing vascular dementia in many cases, although this is not true for everyone. Smoking, high blood pressure, high cholesterol, obesity and a sedentary lifestyle are all risk factors for dementia. A head scan, usually an MRI, can often detect vascular brain changes; however, a scan alone cannot diagnose dementia. There must also be proven changes in the person’s day-to-day functioning and in their cognitive abilities.

The course of vascular dementia is often less predictable than Alzheimer’s disease. Symptoms may appear at different times, and progression can occur in sudden episodes, often linked to strokes. Smaller strokes are called transient ischaemic attacks, or TIAs.

Symptoms may include a sudden increase in confusion, weakness on one side of the body, difficulty finding words or slurred speech, and changes in coordination or movement. It is important to seek urgent medical help if you notice these signs, particularly if they are new. Regular physical activity, a healthy diet, maintaining a healthy weight and stopping smoking can all help reduce the risk of further vascular changes.

Mixed dementia

Mixed dementia is diagnosed when a person has evidence of more than one type of dementia at the same time. This is most commonly Alzheimer’s disease alongside vascular dementia. As with vascular dementia, the course of the illness may be more unpredictable.

Lewy body dementia

Lewy body dementia, sometimes called dementia with Lewy bodies, is less common than Alzheimer’s disease and vascular dementia. It occurs when abnormal proteins called Lewy bodies develop in the brain. These proteins are built from a substance called alpha-synuclein and accumulate inside brain cells, whereas the amyloid plaques seen in Alzheimer’s disease are made of beta-amyloid and deposit outside of cells.

Symptoms of Lewy body dementia can vary but commonly include changes in mood (especially the appearance of depression), sleep and memory, although memory loss is not usually one of the first symptoms. People with this condition often have symptoms similar to Parkinson’s disease, such as tremor, shuffling when walking and reduced facial expression.

Visual hallucinations are also common, often involving seeing people who are not really there. As I have seen over the years, these experiences can feel very real and may be frightening, although some people are not distressed by them and may even find them comforting when they appear, for example, in the form of a previous pet.

Getting help

It is important that if you or someone you love shows any of these symptoms that they seek prompt help from their GP. Getting a diagnosis opens the door to help from different services. Cognitive-enhancing medication is available for some people (those with Alzheimer’s disease or Lewy body dementia) to help with symptoms and delay progression, and having a diagnosis helps avoid crises and length of hospital stays.

In the next blog we’ll be looking at the memory assessment process and getting a formal diagnosis.

< See all Dementia Care articles from Home Instead

Dr Jane Pritchard is a qualified mental health nurse with over 25 years’ experience supporting people living with dementia and their families. She spent 16 years as a Consultant Dementia Nurse, including ten as an Admiral Nurse. She holds a BSc in Psychology and a Clinical Doctorate, and her research into hope highlights its importance for people living with dementia, challenging the stigma surrounding the condition. Jane is a published author and speaker, and is passionate about amplifying the voice of people living with dementia and helping families live well with the condition.