Emma has been a Registered Dietitian for over 17 years and has experience in adult and paediatric dietetics. She has been the Editor of NHD for seven years, steering the editorial content and supporting the production process. Emma currently works in industry.

Emma Coates, RD

Dementia: it's not all in the mind!

Dementia currently affects more than 55 million people worldwide, and every year there are around 10 million new diagnoses.(1)

Covering a wide range of progressive disorders that affect the brain, dementia is an umbrella term for over 200 subtypes, which include vascular, Lewy body, frontotemporal and mixed dementia. It also encompasses Alzheimer’s disease.(2)

It’s estimated that by 2030, over one million people in the UK will have a diagnosis of dementia and, currently, 1 in 11 people over the age of 65 have dementia in the UK.(3) Around 65% of those living with dementia in the UK are women. (3) Dementia can affect people at any age but it is most common in those over the age of 65.

Dementia Action Week this year falls between the 13th and 19th May. With this in mind, I'm highlighting dementia awareness and the modifiable risk factors in my May blog. You can find resources for Dementia Action Week and can support the Alzheimer's Society's campign here...

The term 'dementia' is used by medical professionals to describe a range of common symptoms, which include problems with or impairment of the following:(4)

Memory loss
Thinking speed
Mental sharpness and quickness
Language, such as using words incorrectly, or trouble speaking
Understanding
Judgement
Mood
Movement
Difficulties doing daily activities

It can impact on someone’s interest in their usual daily activities, emotional health, ability to socialise and their relationships with others. Changes in personality and other personal aspects, such as how they communicate and conduct themselves can become altered. Audio and visual hallucinations can also occur.(4) Symptoms progressively worsen as time goes on and there is no cure at present.(2)

Dementia is the gradual decline in brain function as normal neuron function is progressively impaired, which can be caused by a range of factors.

Type of dementia	Percentage of UK cases	Causes
Alzheimer's disease	50-75%	Accumulation of proteins (amyloid and tau) in the brain, creating amyloid plaques and neurofibrillary tangles. Reduced levels of key neurotransmitters, for example, acetylcholine, also plays a role. Collectively limiting or preventing neurotransmission.
Vascular dementia	Up to 20%	Occurs as a result of reduced blood supply to the brain – commonly due to strokes or ‘mini strokes’, known as transient ischemic attacks (TIAs). VD can also occur due to vascular damage of the smaller vessels in the brain.
Dementia with Lewy bodies	10-15%	Abnormal deposits of protein (alpha-synuclein) occur within nerve cells, known as Lewy bodies. These impair the normal function of the cells.
Frontotemporal dementia	2%	Characterised by progressive degeneration of the frontal and/or temporal lobes, caused by abnormal deposits of protein, for example, tau. This causes brains cells to die and shrinkage of the areas in the brain that are affected.
Mixed dementia	✔	A combination of more than one type of dementia – most commonly Alzheimer’s disease and vascular dementia. (Table adapted from 2,5,6)

Risk factors

Whilst dementia covers a range of conditions, the risk factors for all are very similar. You can’t prevent dementia but you can lower the risk.(2)

Current information from NICE (7) describes the key risk factors for dementia, with age being the strongest risk factor. This is followed by having mild cognitive impairment or learning disability, particularly people with Down’s syndrome being affected.

Other factors play a role, such as genetics and the presence of cardiovascular or cerebrovascular disease, or Parkinson’s disease.

Modifiable risk factors include obesity, hypertension, diabetes, smoking and poor physical activity, which all have a significant impact on increasing risk.

It’s estimated that increasing low intensity activity such as walking, may help to reduce dementia by up to 40%. Smoking is associated with a 50-80% increased risk of dementia, but smoking cessation even in later life can reduce this. Diabetes which is diagnosed in mid- to later life is associated with a 50% risk of developing Alzheimer's disease and vascular dementia. Alcohol consumption of more than 14 units per week is also associated with an increased risk of developing Alzheimer's disease.

Low social engagement and support is also recognised as a risk factor. Being lonely, living with depression or being too stressed are all potential risk factors too.

Key advice for dementia risk reduction includes: (2,8)

Eat a healthy and balanced diet
Stop smoking
Avoid excess alcohol consumption
Monitor blood pressure and cholesterol levels – advise and treat when required
Be active – physically and mentally

Dementia and nutrition

Dementia can have a significant impact on nutritional status and it’s common for people with dementia to experience eating and drinking difficulties as their condition progresses.

Challenges can occur as a consequence of:

Taste and smell changes
Poor appetite
Difficulty in shopping and preparing food
Forgetting to eat and drink
Swallowing and chewing difficulties
Dyspraxia and agnosia
Behavioural problems

Nutritional support can be provided and may include food fortification advice, oral nutritional supplements, texture modification and tube feeding; depending on the patient’s needs following screening and assessment.

Behavioural and environmental intervention can be helpful too. Adaptions during mealtimes can help to improve the experience of eating and drinking, supporting someone to focus on eating and drinking and potentially alleviating behavioural factors that impact on this.

Useful resources

The BDA has a comprehensive overview of the eating and drinking difficulties (9) that can occur with dementia - Eating and drinking difficulties in dementia - British Dietetic Association (BDA)

Our very own NHD archive also has a range of past articles which focus on nutrition and dementia, check these out here - Alzheimer's & dementia (nhdmag.co.uk)

Other useful resources include: