Dementia

What causes dementia?

Scientists are still learning about the brain changes that cause dementia. Different illnesses lead to different changes in the brain.

Dementia mostly affects older people, but younger people can get it too.

Types of dementia

Dementia can be caused by many different diseases. These diseases affect the brain in different ways, resulting in different types of dementia.

There are many others. A person can have more than one type of dementia. For example sometimes people with Alzheimer’s Disease may have vascular dementia too.

How does dementia develop?

New discoveries are being made all the time. We do know a little about what makes some people more likely to develop a dementia:

• Alzheimer’s disease is more common in women
• vascular dementia is more common in men
• untreated blood pressure problems or high cholesterol can be linked to a dementia
• the older you are the more likely you are to develop a dementia
• people with Down’s syndrome are at particular risk of developing a dementia

Things which may reduce the chances of developing a dementia

Is it hereditary?

Researchers are studying whether genes affect the risk of developing dementia. In some cases, dementia can run in families, this is called familial dementia, and it is more common in some types of early-onset dementia.

However, this does not mean dementias are hereditary. One exception is Huntington’s disease, a rare condition that can cause dementia. If a parent has Huntington’s, their child has a 1 in 2 chance of inheriting it.

What difficulties does a dementia cause?

Dementia affects the brain, which controls everything we do. It can cause:

• memory loss: forgetting names, faces, or where things are
• communication problems: trouble understanding or finding words
• disorientation: confusion about time, place, or people
• mood changes
• seeing or hearing things that aren’t there

Dementia affects each person in a different way. Different parts of the brain control different functions, so the symptoms depend on which areas are affected. These changes can make everyday tasks harder and affect the things a person needs or wants to do.

A person with dementia may:

• repeat words or actions
• forget self-care such as washing, changing clothes, or eating
• become distressed or angry

Early signs and symptoms

In the early stages, the person may understand what is happening and feel anxious or vulnerable. They often want to stay independent and do things for themselves.

In the earlier stages the person may have an understanding of what is happening to them. The person may feel vulnerable or anxious and need reassurance and support. They may want to do things for themselves.

They may seem:

• unwilling to try new things
• less interested in hobbies or activities
• slow to understand complex ideas
• more self-focussed
• quick to blame others, for example, for lost items
• uninterested in things around them

What is not a dementia?

Not all memory problems are caused by dementia. Many other illnesses or issues can affect memory and thinking, and some can improve with the right treatment. That’s why it’s important to speak to a doctor.

Example include:

• physical illness, such as infections, thyroid problems, medication side effects, or lack of vitamins
• depression, which can cause poor concentration, forgetfulness, and loss of interest
• sudden confusion, often caused by illness such as pneumonia, heart problems, infections, or medication

If there is a sudden change in someone’s memory or behaviour, get medical advice quickly.

What if someone is worried about their memory?

Talking to family and friends can help. If you notice changes in memory, if it’s getting worse over time, or if familiar tasks are becoming difficult, see a doctor. The doctor can discuss your concerns and may refer you to a specialist service, such as a memory service, for tests and advice.

What can help?

Support and treatment

There is no cure for dementia, but with the right support and treatment, people can live well. Early diagnosis gives time to understand the illness, start treatment, and plan for the future. Clear information and support help the person and their family cope and adjust.

The person-led approach

Seeing the person first and focussing on what the person can still do. This person-led approach helps maintain emotional and social wellbeing. Everyone is unique, and dementia affects people differently. Knowing their background, likes, and dislikes makes support more positive. Remember, the illness affects the brain, difficulties are not under their control. Understanding how the person might be feeling can help with giving them the right support and knowing how to respond.

Sometimes a person with dementia may behave in ways that seem confusing. Often, this is their way of communicating. They might feel frightened, be in pain, or worry about losing independence.

Learning about the person and what might trigger these feelings can help. Try to understand the emotions behind their actions. For example, if they seem frightened, offering reassurance can make a big difference.

Dementia affects each person in a different way. People cope in their own ways and may need different types of support. Support for both the person and their carers or family is very important.

What support is available?

People with dementia, and their family and friends, often have many questions and may feel worried or afraid. They have the right to clear information and support. Help can come from health services, social services, or charities. The type of support available may vary depending on where you live.

This might include:

• memory clinics in Rotherham and North Lincolnshire
• dementia support (Mindset) in Doncaster
• young onset dementia support in Rotherham and Doncaster
• community mental health teams such as community psychiatric nurses
• GP and other health professionals
• social workers or care managers, support workers
• home care services (people visiting to provide support with practical tasks at home), day care
• telecare or technology which can help to keep people independent and help with safety (such as an emergency alarm to let others know when the person needs help, for example, if they have fallen)
• benefits (welfare rights)
• support groups for people and their carers
• The person has a right to have an assessment of their situation and needs and to have support for those needs.

Caring for people with a dementia

Carers are people who support someone with dementia in daily life and provide emotional help. A carer can be a family member, friend, or neighbour. They might:

• offer emotional support
• help with practical tasks like shopping, meals, or dressing
• provide occasional help or regular care
• live with the person and give 24 hours a day, 7 days a week support

Support for carers

Carers play a vital role in the lives of people with dementia. Caring can be rewarding, but it can also lead to stress, tiredness, and feelings of isolation.

Carers need to know they are not alone, support is available. For carers in Doncaster, please see our carers’ support group.

Carers have the right to a carer’s assessment. This helps make sure they get the support they need, such as:

• practical help such as home carers to assist with daily tasks
• time to rest or take a break
• emotional support, for example, someone to talk to or local support groups

Getting the right help can make caring easier and improve wellbeing for both the carer and the person with dementia.

This information was reproduced by the kind permission of Dementia Services Development Centre (DSDC) at the University of Sterling.

Page last reviewed: December 08, 2025
Next review due: December 08, 2026