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Dementia - What is dementia?

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Many people grow into old age without much problem. They enjoy life, they're still active, and their minds and memories are as sharp as ever.

But not everyone is so lucky, and some elderly people will develop dementia.  

What is dementia?

Dementia is a gradual loss of mental ability, resulting in loss of memory, changes in personality, and loss of social ability. Dementia is not a normal part of growing old, and most people never develop it.

Dementia is caused by conditions that damage thinking, memory, reasoning and language. There are many such conditions, some more common than others, including:

  • Diseases and infections that affect the brain, such as Alzheimer's disease or meningitis.
  • Pressure on the brain, for example from a brain tumour.
  • Lack of blood and oxygen supply to the brain, for example due to stroke.
  • Head injuries.

Dementia is most common in those aged over 60, and becomes more common with age. About six in 100 people aged over 65 develop dementia, and this rises to around 20 in 100 for people aged 85 or over. It can develop in younger people, but this is rare, as only around one in 1,000 people under 65 are affected.

Forgetting yourself

There are different types of dementia, but all types of dementia cause similar symptoms. These include:

  • Confusion: the person may become easily confused by new people or new surroundings. Sometimes people with dementia lose track of time and don't know what day it is, or what time of day it is.
  • Changes in mood, behaviour and personality: as dementia develops, the person may become angry or aggressive. They may lose their normal inhibitions and say or do inappropriate or antisocial things. Sometimes this can include inappropriate sexual behaviour.
  • Loss of memory: often, people initially have problems remembering recent events, and past memories can be more easily recalled. This could include the affected person forgetting where they live. When the dementia becomes more developed, however, memories of events further in the past may fade.
  • Loss of interest in life: as dementia develops, people may lose interest in the world and what's going on around them. Simple tasks such as washing, dressing and taking care of themselves may be neglected as they lose enthusiasm for life.

The treatment and progression of dementia

Most types of dementia are permanent and cannot be cured but there are exceptions. For instance, dementia caused by a head injury may be cured by surgery; dementia caused by a vitamin deficiency may be treated with supplements. See Diagnosis and treatment  for more information.

The rate at which dementia progresses varies from person to person, but there are recognised stages. People in the latter stages of the condition will become increasingly frail, and eventually they become totally dependent on others for their care. See 'External links' for a factsheet explaining these stages in more detail.

Caring for someone with dementia

Although you may not classify yourself as a 'carer', you become one through the simple act of caring for someone and helping them to live their life.

A carer can be someone who pops in once a week to clean the house and bring the weekly shopping. A carer could also be someone who lives with the person, and is responsible for all their daily tasks such as cleaning, bathing, dressing, cooking and making sure bills are paid.

Being a carer can be stressful and upsetting, particularly if you do it full time. If your partner, relative or friend frequently forgets things, such as planned meetings, appointments, past events or your name, it can be frustrating and upsetting. You may find that your relationship with the person changes as they become more dependent on you.

Equally, the person you're caring for may feel angry at their loss of independence. These are normal reactions. Try to discuss your feelings with someone you trust.

Taking a break will help you to relax and unwind and deal with your own feelings about the dementia. It is not easy to see the health of someone you care about deteriorating, particularly when it's their mind that's affected. Remember this, and give yourself time to cope with the changes.

If you're caring for someone and are struggling to cope, you can seek help and advice from:

  • District nurses, who can advise you on day-to-day nursing care.
  • Community psychiatric nurses, who can advise on caring for someone with a mental illness.
  • Social services, who can help with care in the home, day-care centres, respite care and benefits.
  • Voluntary organisations. In most areas of the UK, there are organisations that provide support and advice for carers of people with dementia. See 'External links' for more information.
  • For more information, advice and support for carers, see Carers Direct.
Medical Review: January 23, 2009

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