Many people fear losing their mental powers, and the risk increases as we grow older. About 670,000 people in Britain today suffer from dementia. This information sheet tells you what happens to people who are affected, what we know about why it is happen happening, and what treatment is possible. Accurate information can reduce misplaced fears and help people learn more about what the future holds.
Dementia is caused by different illnesses which affect the brain. It may involve loss of memory, the ability to think clearly, to understand words and to recognise people. People with dementia can show personality changes and unusual or distressing behaviour. Symptoms may include:
Often people forget what they meant to do, lose their way in places they know and become confused when using a telephone or working out change. Some people change their eating habits, get dressed in the middle of the night or wander off.
Early in the disease the affected person, their friends and family can help by writing things down and using reminders. Later people often lose the skills they need for everyday life, and may fail to recognise family members. Eventually the brain ceases to direct activities and they become dependent on others. People may become bed-bound and unable to resist infection. The most common cause of death is pneumonia.
The immediate cause is disease in the brain causing loss of nerve cells (neurones). As nerve cells cannot be replaced, the majority of affected people become worse over time.
Dementia is rare before the age of 65, but the risk increases with age. The chances of being affected are:
Most people experience mild memory loss as they grow older, but dementia is not inevitable. Even at 90 years old, most people are not affected.
People who sustain head injuries, with loss of consciousness, in an accident and boxers who become punch-drunk are more likely to develop dementia.
About 200 families in the UK have a strong family link with dementia. Many other people inherit a gene which makes the disease slightly more likely, although in these cases there is probably also some other factor involved.
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Although dementia is more commonly diagnosed amongst people with poor education, people from all backgrounds may develop dementia.
As people with Down's syndrome live longer, a higher proportion than the rest of the population develop dementia in their 50s and 60s.
No significant associations have been found between working environments and dementia. There is no measurable risk from aluminium saucepans or from drinking tea (which contains aluminium traces).
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There is little evidence to suggest that any measures can be taken to reduce the risk of developing dementia. Factors such as hormone replacement therapy, smoking, drinking wine and taking anti-inflammatory drugs or vitamin supplements have all been suggested. None of these have been proven.
Many people forget things as they get older and fear this is an early sign of dementia. Usually it is not. Dementia typically takes six months or more to become apparent. A husband, wife or relative may be the first to notice a change in the way someone thinks, talks or acts. A doctor or other professional uses verbal tests to judge whether memory and mental ability are declining, and repeats the tests after a few months to see if there is any change. Scans can show and exclude treatable diseases such as tumours and whether critical areas of the brain are shrinking.
A diagnosis can be accurate in 80 to 90 per cent of cases, but often cannot be confirmed until after death. Diagnosis is important because some causes can be treated and because new drugs are likely to be targeted at particular diseases. Most people are referred to a consultant to confirm diagnosis. People who are seriously concerned should visit their GP and explain their symptoms.
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For most people there is no cure and they progress from mild to moderate to severe dementia over a period of between five and 20 years.
Drugs can help to control depression, difficult behaviour and agitation. New treatments seek to protect messenger chemicals in the brain from being destroyed, and so slow down or delay mental decline. There are good grounds to hope that this treatment will become more effective, although there is no prospect yet of reversing the brain damage that has already occurred.
Because dementia is associated with age, a drug which could delay the start of symptoms would allow more people to reach the end of their natural lives without being seriously affected. If a drug could delay the start of dementia by five years, this would halve the number of people who would be affected before natural death occurs.
Click for more information on new treatments for Alzheimer's disease.
October 1997
Page Text supplied by The Alzheimer's Disease Society of Great Britain