In plain English
A sudden change in a person with dementia almost always has a medical cause. Delirium is treatable. Recognising it promptly and seeking help is one of the most important things a family member can do.
What Delirium superimposed on dementia is
Delirium (ICD-11 6D70) is an acute confusional state developing over hours to days, with fluctuating attention and awareness, usually caused by an underlying medical problem. In someone with established dementia, Delirium produces a sudden worsening of the dementia: more confusion, more agitation, altered alertness, sometimes hallucinations.
People with dementia are particularly vulnerable to Delirium. Around half of older adults with dementia who are admitted to hospital develop Delirium.
How to recognise it
Key features:
- Sudden onset, over hours or days;
- Fluctuation, often hour to hour;
- Marked attention impairment;
- Altered alertness (drowsy or hyperalert);
- New or worse cognitive impairment;
- Often with new perceptual disturbance (hallucinations, misidentification);
- Sleep-wake cycle disruption.
If a person with dementia suddenly seems much more confused than usual, suspect Delirium first.
Common causes
PINCH-ME:
- Pain (often untreated; observe for grimacing, change in mobility);
- Infection (urinary tract, chest, skin, dental);
- Nutrition and dehydration;
- Constipation;
- Hydration;
- Medication (new medicines, recent dose changes, anticholinergic burden, opiates);
- Environment (recent hospital admission, change of routine, recent move).
Other important causes: alcohol withdrawal, low or high blood sugar, electrolyte disturbance (sodium, calcium), recent fall with head injury, stroke, post-surgery, sepsis.
What to do
Three-step response:
- Recognise: is this a sudden change in attention or alertness from the person's baseline?
- Investigate: PINCH-ME checklist; check temperature; look for symptoms of infection; check medication.
- Escalate: contact the GP or NHS 111 the same day for any new Delirium. Call 999 if there is severe agitation, suspected stroke, fall with head injury, severe physical symptoms, or significant safety risk.
What treatment looks like
Treatment is directed at the underlying cause. Antibiotic treatment for infection, laxatives and fluids for constipation, analgesia for pain, oxygen and treatment for chest infection, IV fluids for dehydration. Supportive measures:
- Reassurance and familiar faces;
- Familiar objects;
- Good lighting (no twilight);
- Hearing aids and glasses;
- Avoid restraints;
- Avoid medicines that worsen Delirium (benzodiazepines, anticholinergics, opiates where possible).
Most Delirium resolves within days to a few weeks of effective treatment. A minority of people have persistent reduction in function from baseline. Recurrent Delirium episodes accelerate dementia progression.
Hospital admission
Where hospital admission is needed:
- Bring a current medication list;
- Bring a Life Story Book or summary;
- Ensure hearing aids, glasses, dentures travel with the person;
- Bring a familiar object or two;
- Family presence at the bedside reduces Delirium severity;
- "This is Me" leaflets (Alzheimer's Society) give hospital staff key information quickly.
Prevention
Several measures reduce Delirium risk:
- Treat infections promptly;
- Avoid unnecessary medication changes;
- Manage pain and constipation actively;
- Maintain hydration;
- Familiar people and routines;
- Hearing aids and glasses always in use;
- Sleep hygiene;
- Early mobilisation after illness or surgery.
Frequently asked questions
How is Delirium different from dementia 'getting worse'?
Delirium develops over hours to days; dementia progresses over months to years. Delirium fluctuates strongly and impairs attention markedly. A sudden change in a person with dementia is Delirium until proven otherwise.
Should I take my parent to A&E?
If there is significant new confusion with physical symptoms (fever, breathlessness, severe pain, fall with head injury) or safety risk, yes. Otherwise NHS 111 or same-day GP review.
Does Delirium go away?
Most Delirium resolves with treatment of the underlying cause within days to a few weeks. A minority of people have persistent reduction in baseline cognition.
Can I prevent recurrence?
Treating infections promptly, avoiding unnecessary medication changes, maintaining hydration, managing pain and constipation actively, and ensuring familiar routines all reduce risk.
What is the This is Me leaflet?
An Alzheimer's Society leaflet that summarises essential information about a person with dementia for hospital staff: name preferences, key conditions, routine, fears, things that help. Useful in any hospital admission.
References
- NICE CG103: Delirium: prevention, diagnosis and management.
- Inouye SK. Delirium in older persons. NEJM 2006.
- Alzheimer's Society. This is Me leaflet.
- World Health Organization. ICD-11 6D70.