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Introduction Alzheimer's disease accounts for approximately 60% of all cases of dementia. The disease typically begins with memory loss, mood swings, and with problems finding the correct words. Later the individual may become more confused, experience mood swings and feelings of sadness or anger. They may feel scared and frustrated and also lose their confidence and interest in life. The cells, nerves and transmitters in the brain are attacked during the course of the disease, the brain shrinks and gaps develop. After death, tangled loops and coils of a fibre-like material of beta-amyloid protein, can be observed in brain tissue. People with Alzheimer's also have a shortage of certain chemicals in their brain which are involved with the communication of messages within the brain. Most cases of Alzheimer's develop in later life. Below the age of 65 it is rare, affecting approximately one person in 1000. Over the age of 65 it affects one in 20. By the age of 80 approximately 1 in 5 are affected. Alzheimer's disease affects around 500,000 people in the UK.
Symptoms The features of Alzheimers disease vary from case to case, but three broad stages can be recognised. Alzheimers disease starts with gradual, almost imperceptible, loss of brain function, usually first noticed as loss of memory. The loss of the ability to perform even simple arithmetical calculations, may be one of the first signs of Alzheimers disease. Initially, there is ordinary forgetfulness that can be compensated for by keeping memo pads and lists. The loss of memory, however, often causes anxiety. Secondly, there is a gradual increase in the severity of the memory loss, particularly for recent events. Sometimes this stage includes an element of confusion and even invention (confabulation) to fill the gaps. At the same time there is progressive loss of awareness of the current time or place (disorientation), with uncertainty even in familiar areas and inability to give the date or even the year. Concentration declines with inability to find the right word (dysphasia). These difficulties cause alarm and frustration, and mood may change suddenly and unpredictably. In the final stage there is severe disorientation and confusion. There may be hallucinations and false ideas of persecution (paranoid delusions). These are usually worst at night. The individual may become demanding, suspicious and sometimes violent. They become liable to ignore personal hygiene. Incontinence of urine and faeces is common. The main signs and symptoms of Alzheimers disease are: Confusion. This may include misunderstanding who or where they are. A significant reduction in memory. This may include forgetting people's names or how to get home. Problems with speech and language. Small differences of meaning are lost, language becomes simplified, and conversation becomes repetitive and often irrelevant. Loss of interest in the outside world. This may mean the person gives up interests and hobbies or is indifferent to social conventions and to the opinions of others. Some individuals with Alzheimer's disease may also experience: Marked emotional swings. Night-time confusion. Hallucinations. Changes in personality. Impaired judgement. Lack of inhibition. Obsessional, repetitive behaviour. Difficulties recognising familiar objects. Changes in eating habits. Some people may also neglect their own personal care and hygiene.
Causes No single factor has been identified as a cause for Alzheimer's disease. It is likely to be a combination of factors: Age is the greatest risk factor for dementia, with most cases affecting people over 65. It appears that there is a clear genetic link in a few families, where the disease appears relatively early in life, although developing the disease in such families is by no means inevitable. In the vast majority of cases however the effect of genetic inheritance appears to be very small. It is a feature of Downs syndrome, and 15% of people with Alzheimers disease have a family history of Downs syndrome. Recent research has concentrated on the gene for a substance called beta-amyloid protein that is found in the tangled fibre masses in brains of people with Alzheimers disease and in those of older people with Downs syndrome. The gene for this protein is on chromosome 21. This is the same chromosome of which an extra copy is present in every body cell of people with Downs syndrome. Environmental factors are being studied but nothing has been clearly identified. The concerns concerning aluminium causing Alzheimers disease have largely been discounted. It has also been suggested, but without any convincing clinical evidence, that mercury in dental amalgam might be responsible for causing Alzheimers disease. People with severe head or whiplash injuries appear to be at increased risk of developing dementia. Research has also shown that people who smoke and those who have high blood pressure or high cholesterol levels increase their risk of developing Alzheimer's.
Diagnosis Alzheimer's disease cannot be diagnosed with total certainty during someone's lifetime. It is characterised by damage ('plaques' and 'tangles') seen in and around brain cells. The diagnosis of Alzheimers disease involves making a distinction between this and other forms of dementia. Dementia is a syndrome of failing memory and progressive loss of intellectual power owing to continuing degenerative disease of the brain. Between half and three-quarters of all cases diagnosed as dementia are due to Alzheimers disease. There may be other conditions causing dementia and which can be treated. Standard diagnostic tests include intelligence testing, a full medical history, careful examination, and a computerised tomography (CT scan) of the brain.
Treatment There is no known cure for Alzheimer's disease, treatment is based on reducing symptoms. There are some drugs that seem to delay progress of the disease. The National Institute for Clinical Excellence (NICE) has reviewed three drugs, donepezil, rivastigmine and galantamine, and has decided that they are of some value in certain patients with early Alzheimers disease. They should be continued only if the patient improves or at least does not become worse, and patients must be reviewed every six months. Medical researchers are currently looking at other medical treatments including anti-oxidants, brain stem cell therapy, and a vaccination to stop the build up of plaques in the brain. Much can be done with mood-controlling drugs (tranquillisers) and other forms of medication to reduce behaviour problems and ensure sound sleep. Alternative therapies such as music therapy, aromatherapy and reminiscence therapy may be helpful to some people. It is also helpful to give the person the choice to be alone or with others. It seems that gentle encouragement to use the brain and keeping the environment quite stimulating is a good idea. But it is important not to overwhelm people with demands that may only frustrate them if they cannot meet them. Despite claims that the herbal supplement Ginkgo Biloba helps memory and concentration, a recent research trail has proved it does not improve the mental abilities of older people.
References Further reading: Ginkgo does not enhance memory. NeLH report on clinical trail. Memory and dementia. Royal College of Psychiatrists. Guidance on the Use of Donepezil, Rivastigmine and Galantamine for the Treatment of Alzheimer's Disease. NICE. Clinical and cost-effectiveness of donepezil, rivastigmine and galantamine for Alzheimer's disease: a rapid and systematic review. Clegg A et al. Health Technology Assessment 2001, volume 5, number 1. Dementia - diagnosis and treatment. Bandolier 1998, issue 48, page 2. The effect of different diagnostic criteria on the prevalence of dementia. Erikinjuntti T et al. New England Journal of Medicine 1997, volume 337, pages 1667-74. Sources of variability in prevalence rates of Alzheimer's disease. Corrada M et al. International Journal of Epidemiology 1995, volume 25, pages 1000-5. Donepezil, Rivastigmine and Galantamine for the Treatment of Alzheimer's Disease. Technology Appraisal Guidance No 19. 2001 Galantamine for Alzheimer's disease (Cochrane Review). Olin J, Schneider L. The Cochrane Library, Issue 1, 2002. Selegiline for Alzheimer's disease (Cochrane Review). Birks J, Flicker L. The Cochrane Library, Issue 1, 2002. Donepezil for mild and moderate Alzheimer's disease (Cochrane Review). Birks JS et al. The Cochrane Library, Issue 1, 2002. Rivastigmine for Alzheimer's disease (Cochrane Review). Birks J et al, The Cochrane Library, Issue 1, 2002. Thiamine for Alzheimer's disease (Cochrane Review). Rodrguez-Martn JL et al. The Cochrane Library, Issue 1, 2002. Physostigmine for Alzheimer's disease (Cochrane Review). Coelho Filho JM, Birks J. The Cochrane Library, Issue 1, 2002. Efficacy and safety of Nicotine on Alzheimer's disease patients (Cochrane Review). Lpez-Arrieta JM et al. The Cochrane Library, Issue 1, 2002. Vitamin E for Alzheimer's disease (Cochrane Review). Tabet N et al. The Cochrane Library, Issue 1, 2002. Statins for the prevention of Alzheimer's disease (Cochrane Review). Scott HD, Laake K. The Cochrane Library, Issue 1, 2002.
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Glossary Blood Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.
Brain The brain controls thought, memory and emotion. It sends messages to the body controlling movement, speech and senses.
Tissue Body tissue is made up of groups of cells that perform a specific job, such as protecting the body against infection, producing movement or storing fat.
Cholesterol Cholesterol is a fatty substance made by the body that lives in blood and tissue. It is used to make bile acid, hormones and vitamin D.
Psychiatrist Psychiatrists are doctors who treat mental and emotional health conditions, using talking and listening methods.
Chromosome Chromosomes are the parts of a body cell that carry genes. A human cell usually has 23 pairs of chromosomes.
Gene Genes contain information that you inherit from your parents, such as eye or hair colour. They are carried by chromosomes.
Vaccination Vaccination or immunisation is usually given by an injection that makes the body's immune system produce antibodies that will fight off a virus.
Genetic Genetic is a term that refers to genes- the characteristics inherited from a family member.
Stool Stool (also known as faeces) is the solid waste matter that is passed from the body as a bowel movement.
Hallucination Hallucinations are a sensory experience in which a person sees, hears, or feels something or someone that isn't really there.
Delusions If someone is suffering from delusions, they have lost touch with reality and may experience hallucinations.
Anxiety Anxiety is an unpleasant feeling when you feel worried, uneasy or distressed about something that may or may not be about to happen.
Incontinence Incontinence is when you pass urine (urinal incontinence), or stools or gas (faecal incontinence), because you cannot control your bladder or bowels.
High blood pressure Hypertension is when the pressure of the blood in your bloodstream is regularly above 140/90 mmHG.
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