Neurology: Dementia and Cognition Disorders (Complete)

• Assessment: What is Dementia? | Assessing Memory Problems | Mild Cognitive Impairment | Treatable Contributors and Mimics | Risk Factors and Prevention
• Types of dementia: Alzheimer's Disease | Drug Treatment for Alzheimer's Disease | Vascular Dementia | Dementia with Lewy Bodies | Frontotemporal Dementia | Rapidly Progressive Dementia and CJD | Other Causes of Dementia | Young-onset Dementia
• Living with dementia: Behavioural and Psychological Symptoms | Capacity, Consent and the Law | Care, Hospital Admission and End of Life
• Revision: Drug Reference Table | Spot the Diagnosis | Exam-style Scenarios | Key Points | Guidelines and Further Reading

🧠 Dementia affects about 1 million people in the UK and is the leading cause of death in England and Wales. A good diagnosis opens the door to treatment, support, planning and research. Most of the work of dementia care is not drugs but understanding the person, supporting carers, and avoiding harm. Delirium is covered in the Neurological Emergencies chapter.
Your four questions for every patient: Is this dementia, or delirium, depression or a drug effect? Which type is it, as this changes treatment (especially antipsychotic safety)? Are there treatable contributors (hearing, vision, B12, thyroid, anticholinergic drugs)? What matters to the person and their carers, and are future decisions planned?

What is Dementia?

Definition: A progressive decline in cognition (memory, language, attention, executive function, visuospatial skills, behaviour) that is severe enough to affect daily life, in a person who is fully alert.

• Dementia is a syndrome, not a single disease. The main causes in the UK:
  • Alzheimer's disease - about 60%.
  • Vascular dementia - about 15–20%.
  • Mixed Alzheimer's and vascular - common in older people.
  • Dementia with Lewy bodies and Parkinson's disease dementia - about 10–15%.
  • Frontotemporal dementia - about 2%, but a major cause under 65.
• Severity:
  • Mild - independent with some help (finances, appointments).
  • Moderate - needs help with daily tasks; behavioural symptoms more common.
  • Severe - dependent for personal care; communication and mobility lost.
• Delirium vs dementia:
  • Delirium - acute onset (hours to days), fluctuating, inattention, altered alertness.
  • Dementia - gradual onset over months to years, with attention preserved until later.
  • The two often occur together - dementia is the biggest risk factor for delirium. Don't diagnose dementia during delirium; reassess when recovered.

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Assessing Memory Problems

History - from the patient and an informant (family members often notice more):

• Onset, progression (gradual, stepwise, rapid), first symptoms.
• Which domains: memory (repeating questions, losing items), language (word-finding), executive (planning, finances), visuospatial (getting lost), behaviour and personality.
• Function - driving, finances, medicines, cooking, shopping.
• Mood, sleep, hallucinations, falls, parkinsonism, continence.
• Drugs - especially anticholinergic load, benzodiazepines, opioids; alcohol.
• Vascular risk factors; head injury; family history; education and occupation.
• Safety - driving, cooking, wandering, scams, firearms.

Cognitive testing:

• Brief tools for primary care and wards: 6-CIT, Mini-Cog, 10-point cognitive screener, AMTS.
• More detailed: MoCA, ACE-III (Addenbrooke's) - memory clinics.
• Interpret by education, language, culture, hearing and vision. A normal score doesn't exclude early dementia, especially in highly educated people or frontal disease.

Examination: Parkinsonism, focal signs, gait, hearing, vision, mood, frailty.

Tests (NICE NG97):

• Bloods: FBC, U&E, LFTs, calcium, glucose and HbA1c, TFTs, B12 and folate. Consider ESR or CRP, syphilis and HIV if risk factors.
• Exclude delirium (e.g. urine and infection only if symptoms).
• Brain imaging - CT or MRI - to exclude other causes (tumour, subdural, NPH) and help with subtype (vascular changes, hippocampal atrophy).
• Refer to a memory clinic (or specialist service) for diagnosis.
• Specialist tests when the subtype is uncertain:
  • FDG-PET or perfusion SPECT.
  • DaTscan (dementia with Lewy bodies).
  • CSF biomarkers - low amyloid-beta 42, raised total and phosphorylated tau (Alzheimer's).
  • Amyloid PET.
  • Blood biomarkers (e.g. p-tau217) are being introduced.
• EEG only if CJD, seizures or delirium are suspected.

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Mild Cognitive Impairment

• What it is: Cognitive decline greater than expected for age, shown on testing, but daily function is largely preserved.
• Types:
  • Amnestic MCI (memory) - higher risk of Alzheimer's disease.
  • Non-amnestic MCI.
• Outlook:
  • About 5–15% a year progress to dementia.
  • Many stay stable or improve - especially if depression, sleep problems or drugs were contributing.
• Management:
  • Treat contributors (mood, sleep apnoea, hearing, drugs).
  • Manage vascular risk.
  • Exercise; social and cognitive activity.
  • Review over time.
• Cholinesterase inhibitors don't help MCI - don't prescribe them for it (NICE).
• Subjective cognitive decline - memory worries with normal testing; often anxiety or stress. Reassure and review.
• "Functional cognitive disorder" - attention and memory lapses linked to anxiety, pain, fatigue or overload. Patients often attend alone, and give detailed accounts of their memory failures.

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Treatable Contributors and Mimics

Truly "reversible dementias" are rare, but many treatable factors make cognition worse:

• Depression - "depressive pseudodementia": "don't know" answers, poor effort, low mood, rapid onset. It can also be an early sign of dementia.
• Drugs:
  • Anticholinergics - oxybutynin, tolterodine, amitriptyline, chlorphenamine, promethazine, hyoscine, procyclidine, many others. Use an anticholinergic burden score (e.g. ACB).
  • Benzodiazepines and Z-drugs.
  • Opioids; antiepileptics; antipsychotics.
  • Polypharmacy.
• Hearing and vision loss - mimic and worsen cognitive problems; hearing aids may reduce dementia risk.
• Metabolic - hypothyroidism, B12 deficiency, hypercalcaemia, hyponatraemia, hypoglycaemia (insulin, sulfonylureas), uraemia, liver failure.
• Alcohol - alcohol-related brain damage; Korsakoff syndrome (thiamine deficiency).
• Structural:
  • Chronic subdural haematoma (falls, anticoagulants).
  • Normal pressure hydrocephalus (gait, urinary incontinence, cognition).
  • Tumours (frontal meningioma).
• Sleep - obstructive sleep apnoea, poor sleep.
• Infections - neurosyphilis, HIV.
• Epilepsy - transient epileptic amnesia; non-convulsive seizures.
• Autoimmune - limbic encephalitis (subacute memory loss, seizures, low sodium).

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Risk Factors and Prevention

• Non-modifiable:
  • Age (the biggest).
  • APOE ε4 (one copy raises risk about 3 times; two copies about 8–12 times).
  • Family history and rare genes.
  • Down syndrome (Alzheimer's in most by 60).
  • Female sex (partly longevity).
• Modifiable - the 2024 Lancet Commission estimated that about 45% of dementia could be prevented or delayed by tackling 14 risk factors:
  • Early life: Less education.
  • Midlife:
    • Hearing loss.
    • High LDL cholesterol.
    • Depression.
    • Traumatic brain injury.
    • Physical inactivity.
    • Diabetes.
    • Smoking.
    • Hypertension.
    • Obesity.
    • Excess alcohol.
  • Later life:
    • Social isolation.
    • Air pollution.
    • Untreated vision loss.
• Practical prevention - "what's good for the heart is good for the brain":
  • Treat BP; stop smoking.
  • Exercise; limit alcohol.
  • Manage diabetes and cholesterol.
  • Hearing aids; cataract surgery.
  • Stay socially active; head protection.

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Alzheimer's Disease

What it is: A neurodegenerative disease with amyloid-beta plaques and tau neurofibrillary tangles, starting in the medial temporal lobe (hippocampus) and spreading. Pathology begins 15–20 years before symptoms.

Typical presentation:

• Gradual, progressive short-term (episodic) memory loss - repeating questions, forgetting recent events and conversations, losing things; older memories preserved at first.
• Word-finding difficulty.
• Visuospatial problems - getting lost.
• Difficulty with planning and finances.
• Reduced insight; apathy; depression.
• Later:
  • Apraxia (difficulty with tasks such as dressing).
  • Agnosia (not recognising faces and objects).
  • Language decline.
  • Behavioural symptoms.
  • Incontinence; immobility.
  • Swallowing problems.
  • Seizures in some.

Atypical variants (often younger):

• Posterior cortical atrophy - visual and spatial problems first (difficulty reading, judging distances), memory preserved; often seen first by optometrists.
• Logopenic aphasia - word-finding pauses and difficulty repeating sentences.
• Frontal variant.

Imaging: Hippocampal and medial temporal atrophy on MRI; parietal reduced uptake on FDG-PET.

Genetics: Early-onset familial AD (under 60, autosomal dominant) - APP, PSEN1, PSEN2. Genetic counselling.

Course: Median survival 8–10 years from diagnosis (shorter in older people).

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Drug Treatment for Alzheimer's Disease

Drugs give modest symptomatic benefit (slightly better cognition and function for a period) but don't stop progression (NICE NG97).

• Acetylcholinesterase inhibitors - for mild to moderate Alzheimer's disease (and continued into severe disease if helping):
  • Donepezil 5 mg at night, increased to 10 mg after a month.
  • Rivastigmine (capsules or patch - useful if swallowing is difficult).
  • Galantamine.
• AChEI side effects:
  • Nausea, diarrhoea, weight loss, vivid dreams and insomnia (give donepezil in the morning if so).
  • Bradycardia and heart block → syncope and falls. Do an ECG if there is a slow pulse or heart disease; caution with beta-blockers, digoxin and rate-limiting calcium channel blockers.
  • Urinary incontinence.
  • Muscle cramps.
  • Can worsen asthma, COPD and peptic ulcers.
• Memantine (NMDA receptor antagonist):
  • Moderate AD if AChEIs aren't tolerated or are contraindicated.
  • Severe AD.
  • As an add-on to an AChEI in moderate or severe disease.
  • Dose: 5 mg, increasing weekly to 20 mg daily (10 mg if creatinine clearance is under 30 mL/min).
  • Side effects: dizziness, headache, constipation, drowsiness.
• Primary care can start and continue these drugs once a specialist diagnosis is made.
• Stopping: Don't stop because of disease severity alone. Consider stopping if there are side effects or no benefit, and at the end of life. Watch for deterioration after stopping.
• Anti-amyloid antibodies (lecanemab, donanemab):
  • Licensed by the MHRA for early Alzheimer's disease with confirmed amyloid; they slow decline modestly.
  • They need regular infusions and MRI monitoring for ARIA (brain swelling and microbleeds - higher risk with two APOE ε4 copies and with anticoagulants).
  • NICE does not recommend them for NHS use (final guidance 2025): benefits are too small for the cost and monitoring burden.
• No proven role for ginkgo, vitamin E, statins (for treatment rather than prevention) or HRT for dementia treatment.

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Vascular Dementia

What it is: Cognitive decline caused by cerebrovascular disease.

Types:

• Small vessel disease (the commonest) - widespread white matter damage and lacunar infarcts; gradual decline.
• Multi-infarct dementia - repeated strokes; stepwise decline.
• Strategic infarct - a single stroke in a key area (e.g. thalamus).
• Post-stroke dementia.

Features:

• Slowed thinking (processing speed), poor attention and executive dysfunction, with memory relatively preserved early.
• Apathy and depression; emotional lability.
• Gait problems (small steps, falls), urinary urgency.
• Pseudobulbar signs; focal neurological signs.
• Vascular risk factors - hypertension, diabetes, smoking, AF.

Imaging: White matter hyperintensities, lacunes and infarcts on MRI (or CT).

Management:

• Control vascular risk - BP, lipids, diabetes, smoking, anticoagulation for AF, antiplatelets after ischaemic stroke.
• AChEIs and memantine are not recommended for pure vascular dementia - offer them only if Alzheimer's disease, DLB or PDD is suspected to coexist (mixed dementia).
• Treat depression; physiotherapy for gait.

CADASIL: Inherited (NOTCH3) small vessel disease - migraine with aura, mood problems, strokes in mid-life, then dementia; anterior temporal white matter changes.

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Dementia with Lewy Bodies

What it is: Dementia caused by alpha-synuclein Lewy bodies in the cortex. It is closely related to Parkinson's disease dementia ("one-year rule": dementia before or within 1 year of parkinsonism = DLB; dementia more than a year after established PD = PDD).

Core features (McKeith criteria):

• Fluctuating cognition and alertness - good and bad days, staring spells, daytime drowsiness.
• Recurrent well-formed visual hallucinations - often people or animals; patients may not be distressed.
• REM sleep behaviour disorder - acting out dreams (may precede dementia by years).
• Parkinsonism.

Supportive features:

• Severe sensitivity to antipsychotics.
• Autonomic problems - postural hypotension, constipation, urinary problems.
• Falls and syncope.
• Loss of smell.
• Delusions; depression; anxiety.
• Attention and visuospatial problems are more prominent than memory early on.

Tests: DaTscan (reduced uptake); MIBG cardiac scan; sleep studies; MRI (relative sparing of the hippocampus).

Management:

• AChEIs - donepezil or rivastigmine (NICE) - often help cognition, fluctuations and hallucinations. Galantamine if these aren't tolerated; memantine if AChEIs are unsuitable.
• Avoid antipsychotics where possible - they can cause severe rigidity, falls, confusion, NMS-like reactions and death. If essential for severe distress, use low-dose quetiapine or clozapine with specialist advice. Never haloperidol.
• Parkinsonism - cautious levodopa (it can worsen hallucinations).
• RBD - bed safety; melatonin or clonazepam.
• Autonomic - manage postural hypotension and constipation.
• Falls prevention.

⚠️ Safety Pearl: Before giving an antipsychotic to a confused older person, ask about visual hallucinations, fluctuations, parkinsonism and acting out dreams. Haloperidol can be fatal in Lewy body disease.

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Frontotemporal Dementia

What it is: Degeneration of the frontal and temporal lobes. It usually starts at 45–65, and about 1 in 3 has a family history.

• Behavioural variant FTD (the commonest):
  • Disinhibition - socially inappropriate behaviour, impulsivity.
  • Apathy and inertia.
  • Loss of empathy and sympathy.
  • Compulsive and ritualistic behaviour.
  • Eating changes - overeating, sweet food cravings, putting non-food items in the mouth.
  • Executive dysfunction, with memory and visuospatial skills relatively preserved.
  • Poor insight - family notice the changes.
  • Often misdiagnosed as a psychiatric illness or "midlife crisis".
• Primary progressive aphasias:
  • Semantic variant - loss of word meaning and object knowledge ("What is a giraffe?"); fluent speech; left anterior temporal atrophy.
  • Non-fluent / agrammatic variant - effortful, halting speech with grammar errors; speech apraxia.
  • (Logopenic variant - usually Alzheimer's disease.)
• Overlap with motor neurone disease (FTD-MND) - about 15% of FTD; C9orf72 gene. Look for wasting and fasciculations.
• Genes: C9orf72, MAPT, GRN.
• Imaging: Frontal and/or anterior temporal atrophy (may be subtle early - FDG-PET helps).
• Management:
  • AChEIs and memantine are not recommended - they don't help and may worsen behaviour.
  • SSRIs (or trazodone) may help disinhibition and compulsions.
  • Behavioural strategies; carer support (behaviour is very stressful for families).
  • Driving and financial safety.
  • Speech and language therapy for aphasia.

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Rapidly Progressive Dementia and CJD

Rapid decline over weeks to months needs urgent investigation - several causes are treatable.

• Treatable causes:
  • Autoimmune encephalitis (LGI1, NMDA), Hashimoto's encephalopathy (steroid-responsive).
  • Infections - neurosyphilis, HIV, PML, Whipple's disease.
  • Wernicke–Korsakoff syndrome.
  • Non-convulsive status epilepticus.
  • Tumours - CNS lymphoma, gliomatosis, paraneoplastic disease.
  • CNS vasculitis.
  • Toxic and metabolic - lithium, bismuth, hepatic encephalopathy.
  • Subdural haematoma; NPH.
• Creutzfeldt–Jakob disease (prion disease):
  • Sporadic CJD (about 85%):
    • Age 55–75.
    • Rapidly progressive dementia over weeks to months.
    • Myoclonus (often startle-sensitive); ataxia; visual problems; akinetic mutism.
    • Death usually within a year.
  • Tests:
    • MRI with DWI - cortical ribboning and/or caudate and putamen signal.
    • CSF RT-QuIC (highly specific); 14-3-3 protein.
    • EEG - periodic sharp wave complexes.
  • Variant CJD (linked to BSE in beef): young people, early psychiatric symptoms and painful sensory symptoms, "pulvinar sign" on MRI, longer course.
  • Inherited (PRNP gene) and iatrogenic forms (growth hormone, dura mater grafts, surgical instruments).
  • Management: No cure - supportive and palliative care. Refer to the National CJD Research and Surveillance Unit; infection control precautions for surgical instruments.

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Other Causes of Dementia

• Parkinson's disease dementia - see the Movement Disorders chapter (rivastigmine).
• PSP and corticobasal syndrome - cognitive and behavioural decline with parkinsonism.
• Huntington's disease - executive dysfunction, psychiatric features, chorea.
• Alcohol-related brain damage:
  • Korsakoff syndrome - severe anterograde amnesia with confabulation after Wernicke's encephalopathy (thiamine deficiency). Other abilities relatively preserved.
  • Abstinence and good nutrition can bring partial improvement.
• Normal pressure hydrocephalus - gait apraxia, urinary incontinence and cognitive slowing; enlarged ventricles; may improve with CSF drainage (see the Brain Tumours, Spine and Other Neurology chapter).
• LATE (limbic-predominant age-related TDP-43 encephalopathy) - slow amnestic decline in the very old, mimics Alzheimer's.
• HIV-associated neurocognitive disorder - slowing and apathy; improves with antiretroviral therapy.
• Chronic traumatic encephalopathy - repeated head injury (contact sports): mood, behaviour and cognitive change.
• Down syndrome - Alzheimer's disease often starting in the 40s–50s; baseline assessment in adulthood helps detect change.

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Young-onset Dementia

• Definition: Onset before 65 - about 70,000 people in the UK.
• Different mix of causes:
  • Alzheimer's disease (often atypical) is still the commonest.
  • Frontotemporal dementia.
  • Vascular dementia.
  • Alcohol-related brain damage.
  • Genetic disorders (familial AD, FTD, Huntington's, CADASIL).
  • Down syndrome.
  • Inflammatory, infective and metabolic causes (MS, HIV, Wilson's, autoimmune encephalitis).
• Often missed - mistaken for stress, depression or burnout. Diagnosis takes longer.
• Investigate more widely - MRI, CSF, genetic testing, metabolic screen, EEG.
• Specific needs:
  • Work and employment rights.
  • Finances, mortgages and benefits.
  • Driving.
  • Children and dependants.
  • Age-appropriate services.
  • Genetic counselling for relatives.

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Behavioural and Psychological Symptoms

What they are: Agitation, aggression, restlessness, wandering, shouting, psychosis (delusions and hallucinations), depression, anxiety, apathy, sleep disturbance and disinhibition. Most people with dementia have them at some stage, and they are a major cause of carer stress and care home admission.

Step 1 - find the cause. Behaviour is often communication of an unmet need:

• Pain - use an observational scale (e.g. Abbey Pain Scale, PAINAD); consider a regular paracetamol trial.
• Delirium - infection, constipation, urinary retention, dehydration, drugs.
• Hunger, thirst, need for the toilet, tiredness, being too hot or cold.
• Hearing or vision problems.
• Environment - noise, unfamiliar places, too little or too much stimulation.
• Approach of carers (personal care is a common trigger).
• Depression and anxiety.

Step 2 - non-drug approaches (first line, NICE NG97):

• Person-centred care - know the person's history and preferences ("This is me").
• Structured activities; music; reminiscence; exercise.
• Consistent carers and routines.
• Carer training and support.
• ABC charts (antecedent, behaviour, consequence) to find triggers.

Step 3 - drugs, only if there is severe distress or risk of harm and other approaches have failed:

• Antipsychotics:
  • Increase the risk of stroke (about 3 times), death, falls, pneumonia and faster cognitive decline.
  • Risperidone is licensed for up to 6 weeks for persistent aggression in Alzheimer's disease that causes risk of harm.
  • Use the lowest dose, for the shortest time; review at 6 weeks and try to stop.
  • Discuss risks with the patient and family, and document.
  • Avoid in DLB and PDD.
• Depression - psychological approaches; antidepressants have little evidence in moderate to severe dementia (sertraline, mirtazapine are used; citalopram - QT limit). Avoid tricyclics (anticholinergic).
• Sleep - sleep hygiene, daylight, daytime activity. Avoid hypnotics where possible. Melatonin is not recommended by NICE for sleep in dementia.
• Avoid benzodiazepines except in acute crisis (falls, sedation, paradoxical agitation).
• AChEIs may help hallucinations in DLB and PDD.

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Capacity, Consent and the Law

• Mental Capacity Act 2005 (England and Wales):
  • Assume capacity unless shown otherwise.
  • Give all practical help to support the person to decide.
  • An unwise decision does not mean a lack of capacity.
  • Decisions made for someone who lacks capacity must be in their best interests and the least restrictive option.
• Assessing capacity - it is decision-specific and time-specific. The person must be able to:
  • Understand the relevant information.
  • Retain it long enough to decide.
  • Use or weigh it.
  • Communicate the decision (by any means).
• Planning ahead (while capacity remains - encourage early):
  • Lasting Power of Attorney - for property and financial affairs, and for health and welfare.
  • Advance decision to refuse treatment (legally binding if valid and applicable; life-sustaining treatment refusals must be written, signed and witnessed, with a statement that it applies even if life is at risk).
  • Advance statement of wishes and preferences.
  • Wills.
• Deprivation of Liberty Safeguards (DoLS) - needed when a person lacking capacity is under continuous supervision and not free to leave (e.g. in hospitals and care homes). Due to be replaced by the Liberty Protection Safeguards.
• IMCA (independent mental capacity advocate) - for serious decisions when there is no family or friend to consult.
• Driving:
  • People with dementia must tell the DVLA and their insurer.
  • Many can drive safely in early dementia, with review; formal driving assessment if unsure.
  • Advise stopping if there are safety concerns.
• Scotland and Northern Ireland have their own legislation.

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Care, Hospital Admission and End of Life

• After diagnosis (NICE NG97):
  • A named care coordinator.
  • Information about the type of dementia and its course.
  • Cognitive stimulation therapy (mild to moderate dementia).
  • Carer support - education, respite, carer's assessment. Carers have high rates of depression.
  • Advance care planning early.
  • Social care, benefits (Attendance Allowance), occupational therapy and assistive technology.
• Annual review:
  • Cognition, mood, behaviour.
  • Medication review - anticholinergic burden and deprescribing.
  • Falls; nutrition and weight; continence.
  • Hearing and vision; dental health.
  • Carer wellbeing.
• In hospital:
  • People with dementia have longer stays, more delirium and more falls.
  • Delirium prevention - orientation, glasses and hearing aids, mobilisation, sleep, hydration, avoid catheters and sedatives.
  • Involve family (John's Campaign - carers can stay); use "This is me".
  • Assess pain; support eating.
  • Plan discharge early; avoid moving to a care home directly from an acute ward where possible.
• Advanced dementia:
  • Eating and swallowing difficulties.
  • Recurrent infections (aspiration pneumonia, UTIs).
  • Immobility; pressure sores.
  • Tube feeding (PEG) is not recommended - it doesn't prolong life or prevent aspiration. Careful hand feeding instead, with "eating and drinking with acknowledged risks".
  • Think carefully about hospital admission, antibiotics and CPR - align care with the person's wishes (ReSPECT form).
  • Palliative care: symptom control, comfort, family support.

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Drug Reference Table

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Spot the Diagnosis

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Exam-style Scenarios

1. A 78-year-old woman's daughter reports 18 months of forgetfulness and repeated questions. ACE-III is 72/100. She manages with help.
Answer: Probable mild Alzheimer's disease.

• Bloods (B12, folate, TFTs, calcium, glucose); review drugs (anticholinergics); check hearing.
• Brain imaging; memory clinic diagnosis.
• Donepezil 5 mg, increased to 10 mg (ECG if bradycardic or heart disease).
• Post-diagnostic support; LPA and advance care planning; driving advice.

2. An 80-year-old in a care home with Alzheimer's disease has become aggressive during personal care.
Answer: Behavioural symptoms - look for the cause first.

• Assess pain (Abbey scale), constipation, retention, infection and delirium.
• Change the approach to personal care; ABC chart; person-centred activities.
• Only if severe and risky: low-dose risperidone for up to 6 weeks, with risks discussed and review.

3. A 72-year-old man has 1 year of fluctuating confusion, visual hallucinations and mild parkinsonism. He is agitated in hospital.
Answer: Dementia with Lewy bodies.

• Avoid haloperidol and other antipsychotics.
• Look for delirium triggers; non-drug calming approaches.
• Donepezil or rivastigmine; DaTscan if the diagnosis is uncertain.
• If essential: very low-dose quetiapine with specialist advice.

4. A 66-year-old has become forgetful over 2 months and has jerks when startled. MRI shows cortical ribboning on DWI.
Answer: Sporadic CJD.

• CSF RT-QuIC; EEG.
• Exclude treatable causes (autoimmune encephalitis antibodies, infection).
• Refer to the National CJD Research and Surveillance Unit; infection control; palliative care.

5. A woman with advanced dementia keeps coughing on fluids and has had two aspiration pneumonias. Her son asks for a feeding tube.
Answer: PEG feeding doesn't prolong life or prevent aspiration in advanced dementia.

• Best-interests discussion (check for an LPA or advance decision).
• Careful hand feeding; eating and drinking with acknowledged risks.
• Advance care plan (ReSPECT) covering admission and antibiotics; palliative care.

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Key Points

• Dementia: progressive cognitive decline affecting daily life in an alert person. Delirium is acute and fluctuating with inattention - don't diagnose dementia during delirium.
• Always get an informant history; test cognition; check bloods (B12, folate, TFTs, calcium, glucose); image the brain.
• Review anticholinergic and sedative drugs; check hearing and vision; screen for depression.
• About 45% of dementia may be preventable - BP, hearing, cholesterol, smoking, activity, diabetes, alcohol, social contact.
• Alzheimer's: episodic memory first; AChEIs for mild to moderate; memantine for moderate to severe or add-on.
• AChEIs cause bradycardia and syncope; not for MCI, pure vascular dementia or FTD.
• Anti-amyloid antibodies are licensed but not NICE-recommended.
• Vascular dementia: control vascular risk; AChEIs only if mixed.
• DLB: fluctuations, visual hallucinations, RBD, parkinsonism - avoid antipsychotics; donepezil or rivastigmine.
• FTD: behaviour or language change from 45–65, memory preserved early; SSRIs may help behaviour.
• Rapidly progressive dementia: look for treatable causes; CJD has myoclonus, DWI changes and positive RT-QuIC.
• Behavioural symptoms: look for pain, delirium and unmet needs first; antipsychotics only for severe risk, short-term (risperidone up to 6 weeks).
• Capacity is decision-specific; encourage LPA and advance care planning early.
• No PEG feeding in advanced dementia - careful hand feeding.

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Guidelines and Further Reading

• NICE NG97: Dementia - assessment, management and support for people living with dementia and their carers (2018)
• NICE technology appraisal guidance on lecanemab and donanemab (2025)
• Lancet Commission on dementia prevention, intervention and care (2024)
• McKeith criteria for dementia with Lewy bodies (2017)
• Mental Capacity Act 2005 Code of Practice
• Royal College of Physicians: Supporting people who have eating and drinking difficulties (2021)
• National CJD Research and Surveillance Unit
• Alzheimer's Society; Dementia UK
• BNF - for current doses

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