Dementia Behaviour Changes

Overview

Dementia is a group of brain conditions that slowly damage memory, thinking and everyday skills. 'Behaviour changes' is the name for shifts in how a person acts, feels or responds. Someone who is usually calm may become restless, upset, suspicious or withdrawn. Someone who is usually chatty may go quiet. These changes are a common part of dementia. They are not the person being difficult or 'naughty'. They are often a sign that something is bothering them — pain, fear, tiredness or confusion — or simply that the brain is changing.

Very common. Most people living with dementia will have some changes in mood, behaviour or personality at some point. It is one of the main reasons families first ask for help.

Anyone living with dementia, though changes often become more noticeable as dementia moves into the middle and later stages. It also affects family, friends and carers, who may find these changes harder to cope with than memory loss itself.

Symptoms

Common symptoms

• Restlessness or pacing, especially in the late afternoon or evening (sometimes called sundowning).
• Becoming upset, angry or frightened quickly, sometimes with no obvious cause.
• Repeating the same question or action, or following a carer from room to room.
• Feeling suspicious of others — for example, believing things have been stolen or that a partner is being unfaithful.
• Seeing or hearing things that are not there (hallucinations), or holding strong false beliefs (delusions).
• Withdrawal and lack of interest in things that used to be enjoyed.
• Losing social filters — saying blunt things or behaving in ways that seem out of character.
• Wandering or trying to leave the house, sometimes looking for a former home or a deceased relative.
• Sleeping badly, being awake at night, or sleeping much more in the day.
• Refusing help with washing, dressing or eating.
• Clinging to a carer and feeling very anxious when left alone.

Symptoms in children

• Dementia itself is very rare in children. This section is about children who live with, or visit, a relative who has dementia.
• A child may feel frightened or confused by a grandparent who does not recognise them or who behaves differently.
• Children may become clingy, quiet or angry at home, or worry about their own memory and health.
• Simple, honest explanations and a chance to ask questions help a lot. Let the child's school know if things are hard at home.

Symptoms in older adults

• Restlessness and confusion that get worse in the evening or when light fades.
• Sudden changes in behaviour are often caused by a physical problem such as pain, constipation, a chest or urine infection, dehydration or a new medicine — not by dementia itself.
• Repeated questions about people who have died, or a wish to 'go home' to a place from the past.
• Low mood and loss of interest, which can be mistaken for the dementia getting worse when it may be depression that can be treated.

Causes

Main causes

• Changes in the brain caused by dementia itself, which affect mood, judgement and self-control.
• Pain, constipation, hunger, thirst or tiredness — the person may not be able to tell you about these.
• Infections, especially chest and urine infections, which are a common cause of sudden confusion.
• Side effects or interactions from medicines, or a new medicine started recently.
• A noisy, busy or unfamiliar place, or too little light, which can feel frightening.
• Being rushed, spoken over, or asked to do more than the person can manage.
• Loneliness, boredom or feeling that life has no purpose or routine.
• Depression or anxiety, which are common alongside dementia and can look like withdrawal or irritability.
• Hearing or eyesight loss, which makes the world confusing and can lead to suspicion.

Risk factors

• Dementia at a more advanced stage.
• A change in surroundings such as a hospital stay, moving home or a new carer.
• Other health conditions, such as heart, kidney or lung problems.
• Being in pain or having a hidden infection.
• Hearing or vision loss.
• Some types of dementia affecting the front of the brain, where behaviour changes can appear earlier.
• Carer stress and tiredness, which can make small triggers harder to spot and manage.

When to see a doctor

See a doctor urgently if:

• A sudden change in behaviour or confusion that is new or much worse than usual.
• Behaviour that is putting the person or others at risk at home.
• Signs of infection or pain, as described above.
• You feel you cannot keep the person safe, or you are at breaking point as a carer.

Book a routine appointment if:

• Any behaviour change that lasts more than a few days, even if it seems small.
• Changes in mood, sleep or appetite.
• New suspicion, seeing things that are not there, or repeated upset.
• A new medicine started around the time the behaviour changed.
• You want help understanding why the change is happening and what to do next.

Diagnosis

A doctor will start by talking to the person with dementia and to someone who knows them well. They will ask what has changed, when it started, what makes it better or worse, and whether there has been any illness, new medicine or change at home. The main job is to rule out treatable causes such as pain, infection, constipation, dehydration, depression or a medicine side effect. If nothing physical turns up, they may refer you to a memory clinic or a specialist team.

Tests that may be done

• A full conversation with the person and their carer about what has changed.
• A physical check, including temperature, blood pressure and listening to the chest.
• Blood tests to look for infection, thyroid problems, vitamin shortages, kidney problems and other treatable causes.
• A urine test to check for a urine infection.
• A review of all current medicines, including those bought over the counter.
• Simple memory and thinking questions, done gently and at the person's pace.
• A check of hearing and eyesight, since poor hearing or sight can cause confusion and suspicion.
• A referral to a memory clinic or older people's mental health team for a fuller assessment if needed.

What to expect at your appointment

You may need more than one appointment, and some tests may be repeated. Keep a simple diary for a week or two: what happened, what time of day, what was going on just before, and how long it lasted. This is often the single most useful thing you can bring to the appointment. Nothing about this process is a test of you as a carer.

Treatment

The first step is always to look for and treat a physical cause. After that, the main treatment is calm, understanding care — adjusting routines, surroundings and the way people communicate. Medicines have a limited role and are only part of the plan, never the whole answer.

Self-care at home

• Look for a trigger each time. Ask yourself: could this be pain, hunger, thirst, constipation, tiredness, noise, or feeling lost?
• Keep a simple daily routine, with meals, waking and bedtime at the same times.
• Use calm, short sentences, one question at a time, and allow plenty of time for a reply.
• Avoid arguing about a false belief. Acknowledge the feeling behind it — for example, 'You sound worried, let's sit together' — rather than correcting the fact.
• Reduce noise and clutter, and keep lights on in the evening to ease sundowning.
• Keep familiar objects, photos and routines visible, and label doors or drawers if that helps.
• Encourage gentle activity and daylight during the day, and cut out long naps and caffeine late in the day to help sleep.
• Make the home safer: lock away medicines and sharp items, and consider door alarms if the person wanders.
• Make sure hearing aids and glasses are worn and working.
• Look after yourself too — take breaks, accept help, and tell the doctor if you are struggling.

Medical treatments

Doctors treat any underlying problem first, such as an infection, pain, constipation or a medicine that is no longer suiting the person. Some medicines used in dementia can help with memory and thinking, and occasionally a specialist may prescribe medicine for severe distress, aggression or hallucinations. These are used carefully, at the lowest useful level and for the shortest time, because they can cause drowsiness, falls and extra confusion in older people. They are never a substitute for calm care and a settled routine. All medicine decisions are made by your doctor or specialist team, and you should never start, stop or change any medicine without asking them.

When is surgery considered?

Surgery is not a treatment for dementia behaviour changes. In some cases, a person with dementia may need an operation for another health problem, and the care team will plan ahead to keep confusion and distress to a minimum.

Living with this condition

Life with dementia behaviour changes works best when days are predictable and gentle. Small changes — a night light, a quieter room, a shorter outing, a familiar voice — often make a bigger difference than people expect. Try one change at a time and give it a week before deciding whether it helped. It also helps to tell neighbours, friends and local services what is happening, so people understand and can offer support rather than judge.

Lifestyle tips

• Keep social contact going, even in short, calm visits.
• Build in gentle daily movement, such as a short walk or seated exercises.
• Protect sleep: regular bedtime, daylight in the morning, and less noise and caffeine in the evening.
• Avoid overstimulation — busy shops, loud TVs and large groups can be overwhelming.
• Plan rests after activity, and keep appointments and outings to times of day when the person is usually at their best.
• Keep a diary of what helps, so other carers can follow the same approach.

Diet and exercise

Offer regular meals and drinks through the day, since hunger and thirst can look like irritability. Finger foods and small, frequent snacks can help if the person finds cutlery hard. Encourage drinking, especially in warm weather. Gentle, regular movement — walking, chair exercises or dancing to familiar music — helps mood, sleep and balance, and may reduce restlessness. A doctor, nurse or physiotherapist can suggest safe activity for the person's level.

Mental health and emotional wellbeing

Behaviour changes can be deeply upsetting for everyone. Carers often feel guilty, embarrassed, exhausted or grief-stricken, and may grieve for the person while they are still here. The person with dementia may feel frightened and confused without being able to explain it. These feelings are real and common, and support helps. Talking to your GP, a carers' group or a counsellor is a sensible step, not a last resort. If you or someone you care for has thoughts of self-harm or suicide, contact your local emergency number or a crisis line straight away — you deserve urgent help.

Prevention

Behaviour changes cannot always be prevented, but many can be reduced or avoided. The most powerful steps are spotting and treating pain and infection early, keeping a calm and familiar routine, checking medicines regularly, and making sure hearing and eyesight are as good as possible. Looking after your own health as a carer matters too, because stress makes it harder to notice the small triggers.

Screening programmes

There is no screening test for behaviour changes. Instead, regular reviews of the person's health, medicines, pain, hearing and eyesight help catch problems before they turn into a crisis. Ask your GP or memory clinic about a yearly review.

Complications

If left untreated

• Falls and injuries, especially when the person is restless or wandering.
• Undiagnosed pain or infection getting worse because the person cannot tell anyone.
• Hospital admissions, which can make confusion worse.
• Weight loss and dehydration from refusing food or drink.
• Carer burnout, illness and isolation.
• Strain on relationships and difficult decisions about care being made in a crisis.
• Depression in the person with dementia or in their carer.

Long-term outlook

Behaviour changes tend to come and go, and many improve a great deal once a cause is found and treated. The pattern can shift as dementia progresses, and there may be calmer periods again after a difficult patch. With the right support, most families find ways to manage and still have good days together. Planning ahead — for help at home, respite, and what matters to the person — makes the harder times easier to face.

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