Dementia and delirium screening

What is dementia and delirium screening?

Dementia screening looks at memory and thinking over time, usually through conversation and some simple questions, to see whether a gradual decline is happening.

Delirium screening is a quicker check used when someone becomes confused suddenly, often within a day or two, to work out whether an underlying illness is affecting how their brain is working.

The two are easy to mix up because they can look similar from the outside, but they need different responses: one calls for careful assessment over time, the other for prompt action to find and treat the cause.

Why might I need dementia and delirium screening?

You, or someone close to you, might raise a concern about memory if you've noticed things like forgetting recent conversations, struggling to follow what's being said, losing track of the day or where you are, or finding everyday tasks such as shopping or paying bills harder than they used to be.

Delirium screening tends to come up in a different situation: someone who was previously fine suddenly seems 'not themselves', perhaps more drowsy, agitated, or muddled than usual, often while they're unwell, in hospital, or recovering from an operation.

Family members and carers are often the first to notice this kind of sudden change, since they know the person best.

Screening also helps rule out other explanations for the same symptoms, since memory and thinking problems aren't always down to dementia. Depression, an underactive thyroid, an infection, vitamin deficiencies, and side effects from medication can all cause similar changes, and unlike dementia, many of these can be treated and reversed.

What are the benefits of dementia and delirium screening?

Picking up delirium quickly matters because most cases improve once the underlying cause, whether that's an infection, dehydration, or something else, is found and treated. Left unrecognised, it can take much longer to resolve, and some people don't get back to how they were before.

For dementia, an accurate diagnosis opens the door to the right support, information, and treatment where it's available, and buys your family time to plan ahead together.

Research from the Alzheimer's Society has found that many people wait around 2 years before seeking help, so getting checked sooner rather than later tends to work in your favour.

Screening also catches cases where something else, and not dementia, turns out to be behind the symptoms, which matters because those other causes are often treatable.

Are there different types of screening?

Yes, and which one is used depends on what's being checked and how quickly answers are needed.

For sudden confusion, clinicians often use a short tool called the 4AT. It takes about 2 minutes and looks at four things: how alert someone is, a few basic orientation questions such as their age or where they are, whether they can hold their attention on a simple task, and whether anything has changed suddenly.

A related tool, the Confusion Assessment Method, draws on the same kind of information alongside a broader picture from your history and observations.

For gradual memory changes, a GP will typically use a brief pen-and-paper style cognitive assessment covering memory, concentration, orientation and language. One example, known by the initials GPCOG, is commonly used in general practice for exactly this purpose. If this points to a problem, a more detailed assessment usually follows at a memory clinic, sometimes alongside blood tests or a brain scan.

Do I need a referral for dementia and delirium screening?

For memory concerns, yes: this normally starts with a GP appointment, and if other causes are ruled out, they may refer you on to a specialist in this area, such as a psychiatrist who works with older people, a geriatrician, or a neurologist, often working within a memory clinic.

Delirium screening works differently. It's usually triggered on the spot by a nurse or doctor once someone, often a relative or carer, has flagged that a person seems suddenly different, rather than through a booked referral.

How do I prepare for dementia and delirium screening?

For a planned memory assessment, there are a few things you can do to prepare:

• Bring a familiar face along, since they can describe changes you might not notice yourself and help you remember what's discussed
• Write down what you've noticed beforehand, including when it started, how often it happens, and whether it's got worse
• Bring a full list of your medicines, including anything bought over the counter or any supplements
• Bring your glasses or hearing aids if you use them, so you're comfortable during any tests
• Jot down a few questions in advance, so nothing gets forgotten on the day.

Delirium screening, by contrast, usually happens quickly and without notice, so there's little to prepare beyond being ready to answer a few simple questions, or to share what you've noticed if you're the one raising the concern about someone else.

What happens during dementia and delirium screening?

For a memory assessment, the process usually runs like this:

1. You'll talk through what you've noticed, including when symptoms began and how they're affecting daily life, ideally with a close family member or friend there too
2. The GP checks whether any existing health conditions are being managed properly and reviews your current medicines
3. A short cognitive test follows: a series of simple questions and tasks covering memory, attention, orientation and language
4. Blood tests are usually arranged to check things like thyroid function, vitamin levels, and blood sugar, ruling out other explanations
5. If needed, you may be referred for further assessment or a brain scan to help clarify the diagnosis.

Delirium screening is much quicker. A nurse or doctor will check how alert you are, ask a few simple orientation questions, see whether you can hold your attention on a short task, and ask whether family or staff have noticed any sudden change.

The whole thing usually takes just a couple of minutes, and further checks, such as blood tests or a physical examination, follow to look for the underlying cause.

What happens after dementia and delirium screening?

If dementia is diagnosed, your doctor will talk you through what type it is, if known, what to expect, and the support and treatment available, leaving space for your questions. Ongoing check-ins are then arranged to see how things are progressing and whether your needs have changed.

If delirium is confirmed, the focus shifts to treating whatever caused it, whether that's an infection, dehydration, pain or something else. A calm, familiar environment helps too: clear communication, familiar objects from home, regular food and drink, and clocks or calendars in view can all support recovery.

Most people improve within days of the cause being dealt with, though some take longer, and a small number are left with lasting effects on their memory or thinking.

What are the risks of dementia and delirium screening?

The screening itself, whether it's a conversation, a short test, or a blood sample, carries little to no physical risk.

There are, however, some real limitations worth knowing about:

• Test scores can be affected by someone's education or literacy, so a score alone doesn't tell the whole story
• A single cognitive test isn't enough by itself to diagnose dementia; your doctor weighs it up alongside your history and how you're coping day to day
• Delirium can be mistaken for a worsening of existing dementia, particularly by someone meeting the person for the first time
• Online or app-based memory tests aren't a reliable substitute for a proper assessment, and shouldn't be used to rule dementia in or out on their own