Delirium

Also called Acute confusional state

Sudden confusion caused by physical illness. A medical emergency that is constantly mistaken for dementia.

What it is

If you take one thing from this library, take this one. Sudden confusion in an older person is not dementia getting worse. It is delirium until proved otherwise, and delirium means something physical is wrong right now.

The distinction is about speed. Dementia develops over months and years. Delirium develops over hours and days, and it fluctuates: the person can be lucid at eleven and completely disorientated by four.

It affects around one in five people in hospital, and considerably more in intensive care. It carries a genuinely raised risk of death, and it is missed in more than half of cases because staff assume the confusion was always there.

Signs you might notice

The onset is the diagnostic feature. Ask: was this person like this last week? If no, think delirium.

Attention that will not hold. The person cannot follow a sentence to the end.

Fluctuation through the day, usually worse in the evening.

Hyperactive delirium: agitation, hallucinations, trying to leave.

Hypoactive delirium: quiet, withdrawn, sleepy, not eating. This is the commoner type and the one nobody notices, because a quiet patient causes no trouble.

How it can affect day-to-day life

Almost every cause is treatable, which is what makes missing it such a waste. A urinary tract infection, a chest infection, constipation, dehydration, pain, a new medication, alcohol withdrawal, retention of urine.

Older people with existing dementia are at the highest risk, and are the group whose delirium is most often written off as their baseline.

Recovery is not always complete. An episode of delirium can leave someone permanently less able than before, which is why hours matter.

Supporting someone well

Say the words out loud to the clinician: "this is a sudden change, could this be delirium?" That sentence reliably changes what happens next.

Give the baseline. Nobody in a hospital knows what this person was like last Tuesday except you. Tell them plainly.

Fix the reversible things: fluids, pain relief, glasses on, hearing aids in, a clock and a window, familiar faces, sleep at night and daylight in the day.

Do not argue with hallucinations. Reassure and redirect.

Avoid sedation if at all possible. It usually makes delirium worse and increases falls.

Fiducia Guardian matters here for one specific reason: it holds what normal looks like for this person, so a family arriving at A and E at 2am can show it rather than try to recall it.

Where to get help

Treat sudden confusion as urgent. Call 111, or 999 if the person is very unwell, and use the word delirium.

Ask for the cause to be found and named, not just for the confusion to be managed.

After recovery, ask for a follow-up. Delirium raises the future risk of dementia, and a memory review some months later is reasonable.