Dementia

What is it?

According to the WHO: dementia is a condition that affects memory, thinking and the ability to carry out daily activities, caused by diseases that damage the brain and get worse over time, and it is not an inevitable part of ageing. The NHS describes it as a syndrome (a group of related symptoms) associated with an ongoing decline in brain function that affects memory, speech, thinking, emotions and behaviour.

WHO figures: about 57 million people affected in 2021 (more than 60% in low- and middle-income countries), about 10 million new cases a year, the seventh leading cause of death worldwide, and a global cost of 1.3 trillion dollars in 2019, nearly half of it informal care by family and friends, with informal carers spending about 5 hours a day on average. Women provide 70% of care hours.

Common forms according to the WHO: Alzheimer's disease (60 to 70% of cases), vascular dementia, dementia with Lewy bodies, and frontotemporal dementia. The NHS also lists mixed dementia (more than one type together, most commonly vascular with Alzheimer's).

Causes

According to the NHS: dementia results from the build-up of abnormal proteins that damage nerve cells. In Alzheimer's, amyloid proteins (plaques around cells) and tau (tangles inside them) accumulate, and the level of neurotransmitters including acetylcholine falls.

Vascular dementia results from reduced blood supply to the brain due to narrowing of small vessels, a single stroke or multiple “mini-strokes”. Dementia with Lewy bodies is linked to clumps of alpha-synuclein protein inside cells and affects movement and raises the risk of falls. Frontotemporal dementia is linked to clumping of proteins in the frontal and temporal lobes, is more common at younger ages (about 45 to 65) and may be familial.

Risk factors

Health conditions: high blood pressure, diabetes, obesity, depression, vision or hearing loss, lack of sleep, head injuries, and stroke. Lifestyle factors: smoking, excessive alcohol, physical inactivity, social isolation, and low education. Air pollution is also listed as an environmental factor (WHO).

Early-onset dementia (before age 65) occurs in up to 9% of cases (WHO).

Symptoms

Early signs according to the WHO: frequent forgetfulness and losing things, getting lost or confused in familiar places, disorientation in time, difficulty solving problems, communicating and carrying out tasks, and misjudging distances visually. The NHS adds slower thinking, poorer judgement, loss of interest in activities, and personality change.

Behavioural and mood changes: anxiety, sadness and anger about memory loss, personality change, inappropriate behaviour, social withdrawal, and reduced emotional response (WHO).

How is it diagnosed?

Assessment usually begins with the general practitioner: they ask about symptoms and difficulties with daily activities (personal care, cooking, shopping, paying bills) and rule out other causes of memory problems such as depression, anxiety, delirium due to infection, thyroid problems and medicine effects, through a clinical examination, blood and urine tests and cognitive tests (NHS).

The patient may be referred to a specialist (a psychiatrist expert in dementia, a geriatrician or a neurologist), and brain imaging by CT or MRI and detailed memory tests may be requested (NHS). The referral pathway mentioned here is a description of the UK NHS system and may differ locally.

Treatment

The treatment categories usually used are listed here; this is not a prescription. The doctor chooses the plan according to each person's condition; do not change any medicine or dose without a specialist.

There is no cure according to the WHO. Non-drug interventions include rehabilitation, psychoeducation, physical activity, social interaction and cognitive stimulation. Medicines include: cholinesterase inhibitors (such as donepezil) for Alzheimer's disease, an NMDA receptor antagonist (memantine) in severe cases, blood pressure and cholesterol medicines to prevent vascular dementia, and antidepressants (SSRIs) for depression, which are not a primary treatment for dementia.

The NHS states that early diagnosis may slow progression in some cases and that treatment and support enable many people affected to live active lives.

Follow-up

The NHS states that the doctor arranges regular check-ups to follow progress and new care needs, and that arrangements for the future such as power of attorney and advance care directives are discussed early. These procedures are given according to the UK system and differ legally from country to country.

Prevention

According to the WHO: physical activity, not smoking, avoiding excessive alcohol, a healthy balanced diet, social and mental activity, a healthy weight, controlling blood pressure, cholesterol and sugar, using hearing aids when needed, and reducing air pollution.

Living with it

The WHO offers the iSupport self-help programme, a practical training for carers. It notes that people affected often have their basic rights violated, and that physical and chemical restraints are widely used in care settings despite regulations that protect freedom and choice.

Common questions