Delusions and dementia
Delusions (or strongly held false beliefs) are a common symptom for a person with dementia. Find out what causes delusions, how to support a person who is experiencing them, and how to prevent delusions.
Changes in perception
What are delusions?
Delusions (or strongly held false beliefs) are a common symptom for a person with dementia. They can take the form of paranoia, which makes the person feel threatened, even if there is no or little reason to feel this way. Dementia can make a person suspicious of the people around them.
A person experiencing a delusion may feel that they are being watched, or that someone is acting against them. They may jump to conclusions without much evidence.
For example, if their neighbour has made a nasty comment about them once, they may believe that the neighbour is directing a hate campaign against them. Because of dementia, the person may no longer be able to moderate intense or wild thoughts.
If the person you care for has delusions, this can be very difficult to cope with, especially if they are convinced that you have done something wrong or are trying to harm them. Try to remember that their delusions feel as real to them as your reality feels to you. You will not generally be able to convince a person experiencing delusions that they are wrong or mistaken.
If this is a sudden change, make an urgent appointment with the GP to rule out delirium (which is a medical emergency). If delusions are ongoing and causing distress, the GP may consider a drug treatment.
What causes delusions?
A person with dementia may be unable to put bits of information and memories together correctly, which can lead them to draw false conclusions and believe something that isn’t true.
It is more likely that a person will have delusions over time as their dementia gets worse.
Delusions are more common in dementia with Lewy bodies, and can affect people with Alzheimer’s disease and vascular dementia, particularly in the later stages. They are less common in people with frontotemporal dementia.
How does a person experience delusions?
Delusions tend to be divided into two types. Sometimes a person will believe that someone is trying to do them harm – for example, that someone is trying to steal their money, have an affair, or leave them.
Other times the person will identify something wrongly – for example, that their partner is actually an impostor (Capgras syndrome), or that their home is not really their home.
Delusions often create negative feelings in a person with dementia.
Common delusions include:
- Theft – for example, if a person with dementia can’t find a particular item of clothing, this can cause them to believe it has been stolen. This worry can also lead to them hiding things in unusual places, which in turn leads to more items going ‘missing’.
- A belief that those closest to them are trying to harm them – this could range from believing that a friend is bringing them food because they want to poison them, to believing a partner is being unfaithful.
- Not believing their home to be their real home. This is a delusion if they believe their home to be somewhere they have never lived. However, if they think of home as one they used to live in, often this is caused by ‘time-shifting’.
Supporting a person experiencing delusions
Remember that, for a person experiencing a delusion, their reality is very true for them. If they accuse you, it is natural to feel upset, and to want to tell the person that it is not true.
However, it is often impossible to convince a person who has delusions of the truth. Trying to do so is much more likely to cause them distress than change their mind. There are better ways to support a person who is having delusions.
When discussing a specific delusion with the person:
- Encourage them to talk through their thoughts. It may reveal what is behind their delusion. For example, if they don’t believe their home is their home, it may be due to a recent change in furnishing or unfamiliar people are in their house (such as professional carers).
- Acknowledge their distress and how they must be feeling. Dismissing their concerns, or trying to distract them without acknowledging their concerns first, can cause the situation to escalate and cause them to lose trust in their carer. For example, if the person thinks a carer has been stealing, listen to them. Acknowledge how they must be feeling and suggest supporting them to find the missing items. Gently suggest another activity first, which may distract the person and cause them to forget their delusion.
- Try to gently offer an alternative explanation for what may have happened, and present this as another possibility alongside their delusion, rather than an opposing view.
- Reassure them that their concerns are being taken seriously.
- If the delusion is ongoing and causing significant problems, try ways to avoid further distress. For example, if they believe their friend is bringing over poisoned food and this is causing them to stop eating, look into local meal delivery options or microwave meals they can make themselves. Ask them what they would prefer to do instead.
Preventing or reducing delusions
You can try to prevent delusions by:
- Making set places for things that become lost easily, such as keys or glasses, and keep spares just in case. Make sure items are returned to the same place. For example, always hang keys on the key hook. This can help a person to find things more easily, and may reduce the delusion that missing or misplaced items have been stolen.
- Making sure the person has regular eye tests and hearing checks, to avoid any additional problems caused by sensory impairment. If they hear or see something incorrectly, it can lead to a delusion.
- Avoiding unnecessary changes to their home. Routine and familiarity can help a person to make sense of the world around them, and reduce paranoia. Try to balance the benefits of making a home dementia friendly. with the likelihood of delusions if familiar furniture or items are removed.
- Making sure they have regular medication reviews with a pharmacist or GP. Introducing new medications, or the combination of a person’s medications, can be a cause of delusions.
- Introducing stimulating activity and socialising into a person’s routine. These may help reduce loneliness and isolation, which increase the risk of delusions. For more information see Keeping active and involved.
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