what-is-dementia-by-Sir-Muir-Gray | Spring Chicken

What is Dementia? by Professor Sir Muir Gray

Many people, including many members of the medical profession are confused about dementia and its relationship to Alzheimer’s disease.

If you consult the World Health Organisation (WHO) International Classification of Diseases it says that Dementia is classified as an “organic mental disorder” namely one caused by damage to the brain, as distinct from schizophrenia which is a disorder of the mind.  For diagnosis of dementia the WHO require evidence of:

  • A decline in memory, which can be “mild”, “moderate” or “severe” and
  • A decline in other cognitive abilities characterized by deterioration in judgement and thinking, such as planning and organising and again this deterioration can be graded “mild”, “moderate” or “severe.”

However, the full WHO definition is not easy reading except for scientists so here are some shorter definitions.

Dementia is a condition that some people develop in old age.  This is characterised by confusion and memory problems and its effect on the individual affected is determined by the degree of severity of the dementia, their personality before the dementia developed and by their social circumstances and support.

Alzheimer’s Disease is a disease of the brain of unknown cause and is one of the principal causes of dementia but it seems that there are some people who do develop Alzheimer’s Disease but who develop no symptoms of dementia.

Vascular dementia is the other principal cause of dementia and results from impairments of the supply of oxygen rich blood to the brain, due to disease affecting the arteries of the brain. These two conditions often occur together.

The relationship between these three conditions is best explained with a diagram.

The other causes of dementia are a set of less common diseases such as Picks Disease or some types of Parkinson’s Disease.

There is one more term which we need to explain that you may see in the newspapers or on the web – Mild Cognitive Impairment.

Mild Cognitive Impairment (MCI)

This is a more problematic term.

The American Alzheimer’s Association and the Alzheimer’s Societies of Canada and the UK define it as a disorder that:

  • causes more serious cognitive changes than are observed in normal ageing but are
  • changes not severe enough to interfere with daily life or independent function.

The Alzheimer’s Society UK emphasises that the benefit of diagnosing MCI is that the person can be helped to reduce the risk of developing dementia.  The diagnosis of MCI does not mean that the person will develop dementia but that, in the words of the American Association they are “more likely to develop Alzheimer’s or other dementias than people without MCI.” but the Canadian Society also points out that some people with MCI will improve.

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  • Stigma remains the main hurdle for people with dementia as they are socially positioned across the environment by many as being a non person.

  • When my husband was diagnosed, he didn’t want anybody to know. As time has gone on he still shys away from people knowing. He believes that everybody will treat him differently and be ignored to a greater degree.

  • When my Dad was diagnosed with dementia it was my Mum who wouldn’t tell anyone, she allowed him to continue to drive his car….After he had three accidents I became concerned and spoke to his doctor….It wasn’t until I took him for a hospital appointment that I found out..My Mum told me the appointment was for his legs and said to wait outside. The Doctor sent the nurse out to get me as he was concerned my Parents wasn’t taking the diagnosis seriously…Once I knew it was plain sailing with my Dad as I read every article I could get my hands on and spoke to many specialists in the area..however I had terrible problems with my Mum, she was in denial almost till the end..

  • I was diagnosed with Dementia six months ago, I find night times are the worst, I went to my Doctor and told him I had been having terrible nightmares, his reaction was what do you want me to do its part and parcel of what you have, I really dread going to bed, day times are not to bad, I still manage to do most of my housework, cooking etc, what else can I do, my daughter is wonderful, but she goes out to work, so can’t trouble her to much

    • Do you have a memory clinic nurse? If you are on dementia medication and your dreams started after commencing on them it would be worth letting them know.

  • Please remember that younger people can develop dementia. The article notes that dementia is something people might develop in old age. This is totally missing out a group of people who are struggling for understanding and appropriate support.

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