Medicine of the older adult: Delirium, dementia and mood in older people

• Delirium: What Is Delirium? | Risk Factors and Causes | Recognising Delirium — the 4AT | Finding the Cause | Managing Delirium | Drugs in Delirium | Preventing Delirium
• Cognition and dementia: Delirium, Dementia or Depression? | Cognitive Assessment Tools | Diagnosing Dementia in Older People | Treating Dementia | Behavioural and Psychological Symptoms | Dementia in Hospital and Advanced Dementia
• Mood and mental health: Depression in Older People | Anxiety, Late-onset Psychosis and Alcohol
• Revision: Delirium, Dementia and Mood at a Glance | Spot the Diagnosis | Exam-style Scenarios | Key Points | Guidelines and Further Reading

🩺 Delirium, dementia and mood in older people — page 3 of the Medicine of the Older Person chapter. Delirium affects up to a third of older people in hospital, is missed in most cases, and is linked with death, falls, longer stays and future dementia — yet much of it is preventable. Dementia affects about 1 in 14 people over 65, and depression in later life is common and under-treated. The dementia subtypes are covered in detail in the Neurology chapter on Dementia and Cognition; old-age psychiatry in the Psychiatry chapters.
Your four questions for every confused older patient: Is this new or a change from baseline (delirium until proven otherwise)? What is causing it — usually more than one thing? Is there underlying dementia or depression? How do we keep the person safe and comfortable without sedation?

What Is Delirium?

• Delirium — an acute (hours to days), fluctuating disturbance of attention and awareness, with altered cognition, caused by a medical condition, drug or withdrawal.
• Key features:
  • Inattention — the core feature (can't follow a conversation, months of the year backwards fails).
  • Acute onset and fluctuation — worse in the evening ("sundowning"), lucid periods.
  • Disorganised thinking, disorientation, memory problems.
  • Altered consciousness — drowsy or hyperalert.
  • Perceptual disturbances (visual hallucinations, misinterpretations), delusions (often persecutory), disturbed sleep–wake cycle, emotional changes.
• Types:
  • Hyperactive — agitated, restless, wandering, aggressive, hallucinating — easy to notice.
  • Hypoactive — drowsy, withdrawn, quiet, slow, not eating — commonest in older people, often missed or mistaken for depression or fatigue; worse prognosis.
  • Mixed — switches between the two.
• Why it matters — higher mortality, falls, pressure ulcers, longer stays, functional decline, care home admission, accelerated cognitive decline and a much higher risk of later dementia; distressing for patients and families (many remember it).
• Duration — usually days to weeks; can persist for months in frail people.

Risk Factors and Causes

• Predisposing factors (vulnerability) — age 65 or over, dementia or cognitive impairment, previous delirium, frailty, severe illness, hip fracture, sensory impairment, polypharmacy, alcohol excess, depression, Parkinson's disease, stroke.
• Precipitating factors (triggers) — the more vulnerable the person, the smaller the trigger needed.
• Causes — often several — remember PINCH ME:

  Cause	Examples
  Pain	Fractures, urinary retention, constipation, wounds — often unrecognised in dementia
  Infection	Chest, urine, skin, intra-abdominal, meningitis (rare), COVID-19
  Nutrition	Dehydration, malnutrition, thiamine deficiency (Wernicke's)
  Constipation	Faecal impaction
  Hydration	Dehydration, fluid overload
  Medication	Anticholinergics, opioids, benzodiazepines and Z-drugs, antihistamines, steroids, antiparkinsonian drugs, antiepileptics, digoxin, lithium; withdrawal of alcohol, benzodiazepines, SSRIs
  Environment	Hospital admission, ward moves, catheters, restraints, sleep deprivation, sensory loss

• Also consider — hypoxia, hypercapnia, hypoglycaemia or hyperglycaemia, hyponatraemia, hypercalcaemia, uraemia, liver failure, thyroid disease, urinary retention, MI, heart failure, PE, stroke (rarely causes delirium alone), subdural haematoma, seizures (non-convulsive status), surgery and anaesthesia, terminal illness.

Recognising Delirium — the 4AT

• Screen all older people admitted to hospital (and daily for those at risk) for recent changes in behaviour, cognition, perception, appetite or mobility (NICE CG103).
• 4AT — a rapid screening tool (under 2 minutes, no training, can be used with drowsy patients):

  Item	Scoring	Points
  1. Alertness	Normal (0); clearly abnormal — drowsy or agitated (4)	0 or 4
  2. AMT4 — age, date of birth, place, year	No mistakes (0); 1 mistake (1); 2 or more or untestable (2)	0–2
  3. Attention — months of the year backwards	7 or more correct (0); starts but under 7 or refuses (1); untestable (2)	0–2
  4. Acute change or fluctuating course	No (0); yes — in the past 2 weeks, still present in the last 24 hours (4)	0 or 4

• Interpreting the 4AT — 4 or more — possible delirium ± cognitive impairment; 1–3 — possible cognitive impairment; 0 — delirium or severe impairment unlikely.
• Other tools — CAM (Confusion Assessment Method — acute onset and fluctuation, plus inattention, plus disorganised thinking or altered consciousness), CAM-ICU (ventilated patients), Single Question in Delirium ("Do you think [name] has been more confused lately?").
• Collateral history is key — family and carers know the baseline; "is this how they normally are?"
• Hypoactive delirium is easily missed — drowsy, quiet patients who "aren't eating" need screening.

Finding the Cause

• Delirium is a medical emergency — look for all causes.
• History — onset, collateral history, baseline cognition and function, full medication review (new drugs, dose changes, missed drugs, alcohol and benzodiazepine use), recent falls, pain, bowels and bladder.
• Examination — observations (including capillary glucose and SpO₂), signs of infection, hydration, chest, abdomen, bladder (palpable — bladder scan), rectal examination (impaction), skin and pressure areas, pain (fractures), focal neurology, signs of alcohol withdrawal.
• Investigations:
  • FBC, U&E (sodium), calcium, glucose, LFTs, CRP, TFTs, B12 and folate, blood cultures if febrile.
  • ECG (MI, arrhythmia), chest X-ray, ABG if hypoxic or hypercapnia suspected.
  • Urine culture only if urinary symptoms (don't dipstick in over 65s).
  • CT head — if focal neurology, head injury, a fall on anticoagulants, reduced consciousness without a clear cause, or no other cause found.
  • LP (meningitis or encephalitis suspected), EEG (non-convulsive status).
• Multiple causes are the rule — keep looking after finding the first one.

Managing Delirium

• Treat all causes — infection, dehydration, constipation, retention, pain, hypoxia, electrolytes; stop or reduce causative drugs.
• Non-drug measures — first-line and most important:
  • Reorientation — clocks, calendars, explain where they are and why, consistent staff, introduce yourself.
  • Glasses, hearing aids, dentures in place.
  • Family involvement — familiar faces, photos, extended visiting (John's Campaign).
  • Sleep — quiet, dark nights; avoid night-time observations and ward moves where possible.
  • Mobility — get up and walk; avoid catheters, cannulas and restraints.
  • Nutrition and hydration — help with eating and drinking.
  • Safe, calm environment — side room or bay near the nurses' station, low beds, avoid confrontation, de-escalation.
• Communicate — explain delirium to the patient and family (leaflets), and that it usually improves; include it on the discharge summary (a future risk factor and possible early dementia).
• Capacity — assess decision-specifically; use the Mental Capacity Act (best interests) for treatment; DoLS if restrictions amount to a deprivation of liberty (see page 6).
• Follow-up — check cognition after recovery (about 3 months) — delirium can unmask dementia.

Drugs in Delirium

• Sedation is a last resort — only if the patient is severely distressed or at risk of harm to themselves or others, and non-drug measures have failed.
• Antipsychotics — haloperidol in low dose (e.g. 0.5 mg orally or IM, maximum per local guidance), for the shortest time (usually under 1 week) (NICE CG103):
  • Check the ECG (QT) where possible; risks — falls, parkinsonism, QT prolongation, aspiration, stroke, death.
  • Avoid antipsychotics in Parkinson's disease and dementia with Lewy bodies (severe sensitivity reactions) — if essential, specialist advice; low-dose quetiapine or lorazepam are sometimes used.
• Benzodiazepines — worsen delirium; avoid, except:
  • Alcohol withdrawal (chlordiazepoxide by symptom-triggered or fixed regimen, plus IV Pabrinex for Wernicke's).
  • Benzodiazepine withdrawal.
  • Parkinson's disease or Lewy body dementia where an antipsychotic can't be used (lorazepam, low dose).
• Don't use sedation for "wandering" or to make nursing easier.
• Review daily and stop as soon as possible; never continue antipsychotics after discharge without a clear plan.
• Melatonin — sometimes used for sleep (limited evidence).

⚠️ Safety Pearl — in Parkinson's disease and dementia with Lewy bodies, haloperidol can cause severe rigidity, immobility and death. Also, never stop Parkinson's medicines suddenly (risk of neuroleptic malignant-like syndrome) — give them on time, via NG tube or as a rotigotine patch if needed.

Preventing Delirium

• About a third of delirium can be prevented with a multicomponent intervention (NICE CG103; Hospital Elder Life Program).
• Target the risk factors:
  • Cognition and orientation — lighting, clocks, clear signage, regular reorientation, cognitively stimulating activities, family visits.
  • Dehydration and constipation — encourage drinking, bowel monitoring.
  • Hypoxia — check and treat.
  • Infection — look for and treat; avoid unnecessary catheters.
  • Immobility — early mobilisation, walking aids within reach.
  • Pain — regular assessment (including in people who can't communicate).
  • Medicines — review, especially anticholinergics and sedatives.
  • Nutrition, sensory impairment (glasses, hearing aids, wax), sleep (reduce noise and night-time procedures).
  • Avoid ward moves and moves at night.
• Before surgery — identify high-risk patients (age, dementia, hip fracture), proactive geriatric input, careful anaesthesia and analgesia (regional blocks), avoid benzodiazepines.

Delirium, Dementia or Depression?

• They often coexist — dementia is the biggest risk factor for delirium; depression can cause cognitive problems ("pseudodementia") and is common in early dementia.
• Don't diagnose dementia during delirium — reassess cognition after recovery.

Cognitive Assessment Tools

• Interpret with care — scores are affected by education, language, culture, hearing and vision, and acute illness. Screening tools don't make the diagnosis.

Diagnosing Dementia in Older People

• Dementia — progressive decline in cognition (memory, language, executive function, visuospatial skills) severe enough to affect daily function.
• Mild cognitive impairment — measurable decline without loss of independence; about 10% a year progress to dementia.
• Main types (see the Neurology chapter on Dementia):
  • Alzheimer's disease (about 60%) — gradual memory loss (recent first), then language and visuospatial problems.
  • Vascular dementia — stepwise decline, vascular risk factors, executive problems, gait disturbance.
  • Dementia with Lewy bodies — fluctuating cognition, visual hallucinations, parkinsonism, REM sleep behaviour disorder, antipsychotic sensitivity, falls.
  • Frontotemporal dementia — younger onset, personality and behaviour change or language problems.
  • Mixed — Alzheimer's plus vascular is common in older people.
• Assessment (NICE NG97):
  • History from the patient and an informant; cognitive testing; physical examination; medication review (anticholinergics).
  • Bloods to exclude reversible causes — FBC, U&E, calcium, glucose, LFTs, TFTs, B12 and folate (HbA1c, ESR or CRP; syphilis and HIV serology if risk).
  • Exclude delirium and depression.
  • Refer to a memory service for diagnosis and subtype; structural imaging (CT or MRI) is usually done.
• Advanced age — diagnosis still matters (access to support, planning, treatable contributors, LPA).
• After diagnosis — information and support (dementia advisers), advance care planning while capacity remains, LPA, driving (inform DVLA), safety, carer support.

Treating Dementia

• Acetylcholinesterase inhibitors — donepezil, rivastigmine (oral or patch), galantamine:
  • Mild to moderate Alzheimer's disease; also dementia with Lewy bodies (donepezil or rivastigmine) and Parkinson's disease dementia.
  • Side effects — nausea, diarrhoea, vivid dreams, bradycardia, heart block, syncope (check pulse and ECG if slow), urinary incontinence, weight loss.
• Memantine (NMDA antagonist) — moderate Alzheimer's if AChE inhibitors are unsuitable, or severe Alzheimer's; can be added to an AChE inhibitor; side effects — dizziness, constipation, headache; reduce in kidney impairment.
• Vascular dementia — manage vascular risk factors; AChE inhibitors and memantine only if coexisting Alzheimer's or Lewy body disease.
• Frontotemporal dementia — AChE inhibitors and memantine are not recommended.
• Amyloid antibodies (lecanemab, donanemab) — licensed in the UK for early Alzheimer's but not recommended by NICE for NHS use (modest benefit, ARIA — brain swelling and bleeding — and cost).
• Non-drug — cognitive stimulation therapy (mild to moderate dementia), cognitive rehabilitation, reminiscence, exercise, music, carer training and support.
• Review medicines — reduce anticholinergic burden, avoid sedatives.
• Treat comorbidities — hearing loss (hearing aids), vision, depression, pain, incontinence.

Behavioural and Psychological Symptoms

• Behavioural and psychological symptoms of dementia (BPSD) — agitation, aggression, wandering, shouting, apathy, depression, anxiety, hallucinations, delusions, sleep disturbance, disinhibition — affect most people with dementia at some stage.
• Behaviour is communication — first look for an unmet need or cause:
  • Pain (use the Abbey Pain Scale or PAINAD — consider a trial of regular paracetamol), constipation, urinary retention, infection, hunger, thirst, tiredness, needing the toilet.
  • Delirium (new or worse behaviour).
  • Drugs (anticholinergics, opioids, steroids).
  • Environment — noise, unfamiliar surroundings, boredom, overstimulation, personal care approach.
  • Depression, anxiety, psychosis.
• Non-drug approaches first — person-centred care, structured assessment (ABC charts — Antecedent, Behaviour, Consequence), activities, music, aromatherapy, exercise, staff training, carer support, sleep hygiene, life story work.
• Antipsychotics (NICE NG97):
  • Only for people at risk of harming themselves or others, or with severe distress from hallucinations, delusions or agitation.
  • Risperidone is the only licensed antipsychotic for persistent aggression in Alzheimer's dementia (up to 6 weeks).
  • Discuss risks — stroke, death (about 1.6–1.7 times higher), falls, parkinsonism, sedation, pneumonia, cognitive decline.
  • Lowest dose, shortest time; review at least every 6 weeks; try stopping.
  • Avoid in dementia with Lewy bodies and Parkinson's disease dementia.
• Other drugs — antidepressants (sertraline, citalopram — watch QT and sodium) for depression; avoid benzodiazepines (falls, delirium); AChE inhibitors may help hallucinations in Lewy body dementia.

Dementia in Hospital and Advanced Dementia

• People with dementia in hospital have longer stays, more delirium, falls and functional decline:
  • Use "This is me" (or similar) documents — preferences, routines, how they communicate.
  • Involve carers (open visiting); dementia-friendly wards; avoid ward moves; maintain routines.
  • Assess pain proactively (Abbey); help with eating and drinking.
• Advanced dementia — severe memory loss, minimal speech, dependence for all care, immobility, swallowing problems; often recurrent infections (aspiration pneumonia) and weight loss.
• Eating and drinking difficulties:
  • Assess for treatable causes (mouth problems, dentures, depression, constipation, drugs, delirium).
  • Speech and language therapy — texture-modified food and fluids (IDDSI), positioning, hand-feeding.
  • Tube feeding (PEG) is not recommended in advanced dementia — it doesn't prolong life, prevent aspiration or improve comfort (NICE NG97).
  • Eating and drinking with acknowledged risks — careful hand-feeding for comfort, agreed with the patient's representatives and documented.
• Recognise dementia as a terminal illness — advance care planning, ceilings of care, avoiding burdensome admissions, palliative care (see page 6).
• Carer support — carer's assessment (Care Act), respite, support groups; carer strain is a major cause of care home admission.

Depression in Older People

• Common — about 1 in 7 older people; higher in care homes, after stroke, with chronic illness, pain, bereavement, isolation and disability.
• Presentation is often atypical — physical symptoms (fatigue, pain, weight loss, poor sleep), memory complaints, anxiety, irritability, apathy, withdrawal, poor self-care, refusing food; low mood may be denied.
• Screen — "During the last month have you been bothered by feeling down, depressed or hopeless? Little interest or pleasure in doing things?"; Geriatric Depression Scale (GDS-15), PHQ-9; Cornell Scale in dementia.
• Exclude physical causes — hypothyroidism, hypercalcaemia, B12 deficiency, anaemia, cancer, Parkinson's disease, stroke, drugs (beta-blockers, steroids).
• Suicide risk — older men have high suicide rates; ask directly about suicidal thoughts; risk factors — living alone, bereavement, chronic pain, physical illness, alcohol.
• Treatment:
  • Psychological therapies (CBT, behavioural activation), social interventions (reducing isolation, activities, social prescribing), exercise.
  • SSRIs — sertraline is often first choice in older people (fewer interactions); citalopram (max 20 mg over 65 — QT); watch for hyponatraemia (check sodium at baseline and 2–4 weeks), GI bleeding (add PPI with NSAIDs or anticoagulants), falls.
  • Mirtazapine — helps sleep and appetite; sedation and weight gain; falls.
  • Avoid tricyclics (anticholinergic, cardiotoxic, falls).
  • Continue for at least 12 months after remission in older people (relapse is common); ECT for severe or psychotic depression.
• Psychotic depression — nihilistic delusions (Cotard's), refusing food and fluid — urgent psychiatry.

Anxiety, Late-onset Psychosis and Alcohol

• Anxiety — common, often with depression or physical illness; new anxiety in later life — look for depression, early dementia, drugs (salbutamol, thyroxine excess, caffeine, withdrawal), hyperthyroidism, arrhythmias; CBT, SSRIs; avoid benzodiazepines long-term.
• Late-onset psychosis:
  • Very late-onset schizophrenia-like psychosis — over 60, women, living alone, sensory impairment (deafness), persecutory delusions (e.g. neighbours breaking in) — low-dose antipsychotic, treat hearing loss.
  • Secondary causes — delirium, dementia (especially Lewy body), drugs (levodopa, dopamine agonists, steroids), brain lesions, Parkinson's disease psychosis.
  • Charles Bonnet syndrome — vivid, complex visual hallucinations in people with visual loss (macular degeneration, cataract), with insight — reassurance, treat vision.
• Alcohol in older people:
  • Often hidden; increased sensitivity (less body water, slower metabolism, drug interactions).
  • Causes falls, confusion, incontinence, self-neglect, poor nutrition, depression, interactions (warfarin, sedatives).
  • Screen with AUDIT-C; watch for withdrawal in hospital (CIWA-Ar, chlordiazepoxide — consider lower doses or lorazepam in liver disease or frailty); thiamine (Pabrinex) to prevent Wernicke's encephalopathy (confusion, ataxia, ophthalmoplegia).
• Loneliness and social isolation — linked with depression, cognitive decline and higher mortality — ask about it; social prescribing, befriending, community groups.

Delirium, Dementia and Mood at a Glance

Spot the Diagnosis

Exam-style Scenarios

1. An 84-year-old woman with mild dementia had a hip fracture repair 2 days ago. Tonight she is shouting, pulling at her cannula and trying to climb out of bed. She is on regular morphine and has not opened her bowels since admission. Her catheter was removed this morning.
Answer: Hyperactive post-operative delirium.

• Look for causes — urinary retention (bladder scan), constipation (rectal examination), pain, opioid toxicity, infection, hypoxia, electrolytes (sodium), anaemia, glucose.
• Non-drug care — calm reassurance, family, glasses and hearing aids, remove the cannula if not needed, low bed, enhanced supervision.
• Only if severely distressed or at risk — low-dose haloperidol (0.5 mg), short-term, after checking QT if possible; review daily; record delirium on the discharge summary.

2. A 79-year-old man with Parkinson's disease is admitted with pneumonia and is not swallowing. His tablets were missed for 24 hours. He is now confused, rigid and febrile with a raised CK.
Answer: Delirium with possible parkinsonism-hyperpyrexia (neuroleptic malignant-like) syndrome from missed dopaminergic drugs.

• Restart Parkinson's medication urgently — via NG tube, or a rotigotine patch (dose conversion with the Parkinson's team or pharmacy).
• Treat pneumonia; IV fluids; cooling; monitor CK and kidney function.
• Avoid haloperidol and metoclopramide (use domperidone if an antiemetic is needed); time-critical medicines policy.

3. An 81-year-old woman's daughter says her mother has become forgetful over 18 months — repeating questions, missing bills and getting lost driving. She lives alone. MoCA 19/30. Bloods are normal.
Answer: Probable dementia (likely Alzheimer's disease).