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What is Alzheimer's disease?

What is Alzheimer's?

There are over 100 different types of dementia with Alzheimer's Disease being perhaps the best known. As with most forms of dementia, Alzheimer's involves progressive memory loss (as well as loss of other vital functions) and at present is irreversible.

What causes Alzheimer's?

It is not entirely clear what causes Alzheimer's but there's likely to be more than one contributing factor. On a molecular level, it involves chemical and structural changes to the brain which start killing off brain cells.

Dementia is a progressive condition - it gets worse over time and, along with memory loss, other symptoms can include confusion, loss of speech, depression and severe mood swings. Dementia can appear after the victim has suffered a stroke.

Other causes can include vascular disease, which is when blood flow to the brain is reduced or disrupted, causing a decrease in oxygen which eventually kills off brain cells. Dementia may also be related to another condition such as Parkinson's or Multiple Sclerosis. The exact symptoms depend on the type of dementia.

Memory loss for recently acquired information is common but older information remains perfectly intact. In the later stages, sufferers can retreat into their childhood, replacing the people and context of the present, with those of the past.

This makes complete sense to the sufferer and it may be the way in which the mind attempts to create a coherent world picture as sufferers lose touch with the present

Who gets it?

The overwhelming majority of people with dementia are elderly - over 65 but it can affect younger people too. The Alzheimer's society estimates there are around 750,000 people in the UK currently suffering from some form of dementia and around 18,000 of those are under 65. As people in the Western world live longer it's likely that the numbers of people with some form of dementia will increase.

Can we prevent Alzheimer's?

Since we're not sure of the cause it's hard to know how to prevent it. Studies have linked Alzheimer's both to genetic and environmental factors. Lifestyle choices may be important but research sometimes sends out conflicting messages. For example, some studies show an increased risk of getting Alzheimer's if you smoke but others suggest the opposite, particularly in people who have a gene associated with the disease.

A better understanding of this condition is not for want of effort - there are a staggering number of research papers devoted to understanding dementia - already in 2006 alone, more than 1500 international, peer-reviewed studies have investigated some aspect of Alzheimer's.

What should you do if you think you have Alzheimer's?

Everyone forgets - having a poor memory doesn't mean you have dementia. Memory loss as you get older is common, largely unavoidable and certainly no reason to panic. In fact studies show that your memory slows down in old age and that doesn't necessarily mean it's deteriorating.

In fact research shows that when given more time to answer questions or problem-solve in recall experiments, elderley subjects do just as well as younger people. Memory loss might also be down to conditions other then dementia such as depression, insomnia and in rarer cases, vitamin deficiency.

There are lots of simple exercises you can do to improve basic memory function - go to the improve section of the website, try them and let us know what you think of them. However if you are still concerned then visit your GP who can refer you to a specialist to determine whether the early signs of dementia are present.


My father has been diagnosed with small blood vessel disease, following a month of an extremely painful headache which rendered him bed bound. The pain he felt was caused by a lack of blood getting through the vessels near to the surface of the head. But what is the difference between small blood vessel disease and Alzheimer's? Will my father's memory defintely decline? Over the last year, his personality does seem to have altered slightly in that he is less relaxed about things and gets worked up more easily. On the other hand, my mother and I wonder if we are just imagining this and that really he's fine.

I work in a day centre for the elderly, whom some of the service users have alzheimer's disease. I often see how distressing it is for the family as well as the sufferer. Programmes such as Coronation Street which cover stories of dementia often enlighten people of the disease, and sometimes, recognising such behaviours in someone close. But sometimes, people can be diagnosed of having memory problems, when they are just depressed, and given the correct treatment, solving the problems. Looking after someone I know, they cannot express how they feel, perhaps embarrassment, but instead he becomes aggressive and tearful.I cannot ever imagine a life where I cannot understand basic things in life or not know how to express a simple emotion.

Rosemary Rowberry
I found the most distressing thing was the lack of support from our mental health trust when my husband was diagnosed at 59. I certainly didn't realise that support and help are down to your postcode. I felt that we'd got to go away and get on with it, there's no treatment so what did we expect? Thank goodness for the Alzheimer's Society.

anonymous, age 12
ive allways thought that this desiese was caused by the fact that as you get older that you will have more of your life to remember. so your brain will dispose of any old or new information to make space for more information. on the memory manor show it mentioned that the brain disposes of any unwanted information because it can only hold somuch information.

My grandad suffered from alzheimer's for numerous years before his death. He could not remember any of his family, and often referred to my sister, ( about 8 years old at the time) as hid dead wife. This was all quite distressing, as at the age of 6, i didnt understand why my grandad didnt know me. He did not use my fathers name for years, but strangely, the day before he died, he started re-enacting senarios from his childhood. He really thought he was a child. And then, for the first time in years he called my father (his son) by his name. Why he suddenly knew my father the day beore his death, none of us know.

My mother was diagnosed with Alzheimer's 18 months ago and I am her main carer. There are times when I feel very resentful of this illness for taking 'away' the mother I loved and I think the phrase I heard recently that described it as the 'long goodbye' very apt. I too am worried that it can be hereditary as my mother's mum had it, despite being reassured that this is not the case. Having said all this I have to say the care my mother receives at the day centre she attends is second to none and while helping her also helps me a great deal and they stress the importance of caring for the carers as well.

Kelly Coburn
I am an Occupational Therapist. I work in a day hospital for people with dementia. My role is to stimulate people through activities and to compensate for memory loss/ physical loss through aids/ adaptations/ finding new ways of doing things etc. It is important to note that Alzheiers/ dementia is a physical illness not a mental illness. It occurs when a part of the brain is damaged. There are several different types of dementia that progress at different levels/ speeds. Dementia mainly affects older adults from the age of 60 but cannot also affect other age groups including children. Different types of dementia affects different types of the brain i.e the frontal lobe, the frontal temporal lobe,etc. Different types of dementia has different causes i.e. a blood clot in the brain, a detoriation of a part or the whole of the brain, damaged caused when lewey bodied cells are present, a brain injury etc. There is also such thing as drug/ alchol induced dementia and dementia caused by cdj. Dementia does not only affect memory. It can affect a persons personality, behaviour, communication skills as well as a persons physical health. A person may also loose the ability to swallow, their body may become ridgit and they may suffer from shaking simpilar to parkinson disease. Dementia can affects peoples ability to walk as well. Short term memory is affected before long term memory as people loose the ability to store new information. It is important that people are kept stimulated through activities such as word games, quizes, art and crafts, music, cooking, physical exercise etc. They are then encouraged to use their skills. Sometime verbal and physical prompts are required when carrying out activities. Carrying out activities can also be difficuly the person has poor eyesight or hearing difficulties. Tricks like puting coloured paper under white paper when doing an art project can be used. Speaking clearly and breaking activities down into small tasks are very important. People will not beneifit from activities inless they are interested in them. At home memory prompts can be used but these dont always work. Sensor can also be used to contact family members or the person if there is a problem such as they have left the water running, gas on or fallen from the beds. Voice activated prompts can also be used to remaind a person to take their key with them or not to leave the house at night. I hope this is helpful.

june newcombe
My mother had alzeimers and could not recognise any of her family. She also lost her speech. One Sunday my son found her in the television room watching Songs of Praise and she was singing along to them.

'Dancing with Dementia' by an Australian woman Christine Bryden is an inspiring book about someone who led a wonderfully useful life with frontal lobe dementia.

My father died a few years ago after suffering froma type of dementia similar to Alzheimmers - multi-infarct dementia. I am grateful that he never forgot who I or other family members were. One of the things I found fascinating was how much better he could communicate when on the phone than when talking face to face - it was as if by concentrating on one sense alone he became much sharper.

Astrid Sharkey
My mother started on a long Alzheimer's journey when she was 70. She has been in a home for10 years and she's now 87. In the initial stages you could tell she felt a great deal of stress, I felt so sorry for her and cross with myself for finding her repetition, and her difficulty in accomplishing simple tasks, irritating. 3 years ago she broke her hip when she fell out of bed. Following an operation she was sent back home - probably to die in familiar surroundings. She's still with us, though. She can't walk, can't feed herself, and she is incontinenet. However, she is mostly happy and clearly has a strong will to live. If she's feeling chatty you can tell that she understands everything that you are telling her but that she cannot find the right words to reply. She will talk in a very Lewis Carroll language which has perfectly normal inflections and emphases. Some of the words have great charm - I sometimes write them down. On other days I'll talk to her about friends I've seen and she'll tell me that she's just seen them too - sometimes at a party! And in her head she has. We think that in her mind she leads a very active social life and that's what keeps her going.We are also intigued by the fact that, very occasionally she becomes her old self. You know immediately by her tone of voice when this is going to happen. It's as though a curtain is temporarily lifted and old conversations can resume. On these days, we can get out photo albums and really chat about them - people and friends especially. I feel that those days are an unexpected privilege - can anyone account for this?

My mother was diagnosed with senile dementia 7 yrs before she died, but she never knew what was wrong with her as once she had deteriorated it was too late to explain it to her. I belive the shock of my father dying from cancer after 49 yrs of marriage caused the start of the dementia. We managed to keep her in her own home with help up to the last 2 years of her life. It was the most awful thing to watch this vibrant wonderful woman deteriorate in such a way.

My grandmother recently died and suffered from alzeimers in her final year. It was very sad to see the deterioration in her. Just as she was beginning to decline, a family secret came out - that her husband was not my mum's dad, but that my mum was an illegitimate child in 1940. Unfortuantely, we were never able to get any more information from her about this, even though the disease tends to leave older memories alone. Upon doing research into trying to understand what happened, it transpired that my nan suffered tremendously at the time because of the stigma associated with being a single mum. This must have been a very painful time for her and she had probably spent her whole life trying to forget it. She was finally blessed with a disease that helped her to do this. The remarkable thing was, that once she had contracted alzheimers, she was alot more cheery and seemed alot more at peace. It was almost as if she had forgotten why she was bitter at life. It was an unusual and unexpected good thing to come from the disease.

My father in law suffered from Alzheimer's for 5 years before he died aged 85. As I work in a health-related field I tried to lay my hands on as much information as possible for my husband and his family. We were very interested in the theory that traumatic events in the past could potentially set off Alzheimers. My father in law was a merchant seaman in World War II and his ship was torpedoed off the coast of Russia and the surviving crew members were in icy waters for a couple of hours before they were rescued. We wondered if this kind of event lodged in his memories would eventually start the awful decline that is Alzheimer's? As he regressed it was this time in his life which became the 'reality' and his wife often found him out of bed at night 'on watch'.

My dad was diagnosed with Alzheimers about two and a half years ago at the age of 57, and at that point was advised to cram in everything that he wanted to do in the next 5 years. He's now on anti-depressants and cannot do most things that once came easily to him. The whole thing is really sad and I feel as if I'm slowly losing him. Sometimes I look forward for when he won't know what is going on, as it may be some kind of peace for him. When I find my memory failing me now I get anxious that I might go the same way - and I'm only 24!

Jenny Knight
My father had Alzheimers and died three years ago. I watched an intelligent, articulate man with great enthusiasm for life deteriorate into a sad soul who recognised none of his family and finally lost all capability and dignity. It is the cruellest disease and yet on a scientific level completely fascinating; where did the essence of my father go? What happened to his consciousness? There was only a short period - perhaps 2 months or so -when he realised "something was wrong" and would ask what was happening to him. After that, he had no awareness at all that he was ill. Most distressingly, he began to have long term recall of incidents in the Second World War that he had never communicated to the family, though his short term memory disappeared altogether. I can also relate to the experience of Anne, above, in that my father was also the most placid and gentle of men, and yet for a time during his illness became uncharacteristically agressive. That phase passed.

Rami (web team)
re organic versus psychiatric: My understanding of the difference is that doctors tend to class a brain disorder caused by a physical process as organic. Whereas they tend to see a mental illness involving more of a chemical imbalance, as psychiatric. So in this case, it's about a physical condition (brain cells dying for instance) that can create mental changes (the symptoms of Alzheimer's) as opposed to a lack of a certain neurotransmitter (such as serotonin) which is linked to depression. Of course, nothing is ever so simple and when you get right down to it, it's all physical but that's for another discussion.

I found that very informative I would like to know why what does it mean when I was told that AD is organic and not the same as a mental illness.

Having the experience of my mother suffering from Alzheimer's disease, I often hear people say. I think I've got Alzheimer's disease when they say they've forgotten where they have left something eg car keys. I tell them an Alzheimers patient wouldnt even know what to do with the keys even if they had found them..

My mother-in-law had a dementia similar to Alzheimer's and it was very distressing for the whole family to see her deteriorate. However a lot of the time she seemed to be very happy and content, once she had got past the frustrating stage of knowing that she couldn't remember something.

Anne Hadfield
Ruths husband must be very lucky. He obviously has quite a lot to say, as being apposed, he probably is not!!!!

Valerie Bowker
My mother died eighteen months ago from Alzheimer's. I feel its onset was after a bad fall down an escalator when she received a back bang on the head. I noticed she starter having hallucinations immediately after the accident and these continued until she died. She was diagnosed with Alzheimer's just six months after the accident. As far as I am aware there has not been another case in the family, although my mother died at 81 both her parents were in their 80's when they died and as far as I am aware neither suffered from the complaint. Could a bang to the head be a contributory factor in this case?

My mother had Alzheimer's and used to rehearse her answers to the predictable questions asked of her by the doctors. This was at the stage when she knew her memory was going and was desperately trying to cope with that fact. So sad!

My mother had Alzheimer's, and since then every time I forget something I panic.It is the genetic link that worries me. Does a person who has Alzheimer's desease recognise that they have it in the early stages?

My father is recently diagnosed as having Alzheimers, but the drugs don't work. Is there anything else that may help. And why has he become short tempered, where before he was such a placed man?

Rami (website team)
Sadly, the diagnosis of dementia and in particular of Alzheimer's is complicated and requires quite a careful process to rule out a host of other conditions. For anyone unsure or in need of more information about how to acquire a diagnosis, a good place to start - apart from your own GP - is The Alzheimer's Society. Click on the link above.

Elva Knott
I looked after my mother for 10 years with Alzheimer's and I thought the memory tests that she had did little to diagnose her condition and caused distress. They mainly tested semantic memory which I felt was a very unreliable way of testing anyone.

John (site producer)
The only sure way to find out is to go back to your doctor and ask him.

My husband was tested for Alzheimer's disease about a year ago and the doctor said he didn't have alzheimer's but that he had the opposite of Alzheimer's. What do you think that statement meant?



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