Introduction
Dementia is an acquired, progressive impairment of overall mental function affecting memory, cognition (understanding) and personality without any clouding of consciousness. Though it can affect people at any age, it occurs mainly in the older age groups. About 5% of people over 65 years suffer from dementia and about 20% of those over 80. There are twice as many women with dementia as there are men.
Causes of Dementia.
The principal cause of dementia is the degenerative condition of the brain known as Alzheimer's disease. Formerly, when it affected people under 65 years it was called pre-senile dementia and in those over 65, senile dementia. These terms are now less in use. The second most common cause is vascular disease of the brain which goes under the term multi-infarct dementia, often referred to in the past as arteriosclerotic dementia.
People suffering from conditions such as Huntington's disease or cerebellar ataxia frequently develop dementia as part of the illness. Less commonly it is associated with other conditions such as AIDS, Parkinson's disease and multiple sclerosis.
Whatever the underlying cause, the outcome of dementia is the same. Therefore, the same considerations apply to the determination of needs in any particular type of dementia irrespective of its cause.
Dementia causes impairment of memory, especially of recent short-term memory. A person may not remember where she has just put something or what she is about to do, yet retain memory of events long past. Recent memory impairment results in difficulty with shopping and even with simple tasks such as making a cup of tea. Frequently, the person will ask the same question repeatedly. This repetitive questioning can be very wearing for the carer. More severe memory loss leads to failure to change clothing and to neglect of personal hygiene.
The person may lose the ability to orientate in time and space, being unsure of the day or date, where she is, or who people around her are. This can contribute to wandering or aggressive behaviour.
Cognitive function, that is the ability to understand, is affected and there is a reduced ability to acquire new information. This often becomes apparent when the place of residence is changed, the person being unable to cope with the new environment. There is loss of understanding of what is read or heard and so the person has little knowledge of current affairs. The ability to calculate is affected so she cannot cope with money.
Judgement is also affected, leading to exposure to danger out of doors with traffic and indoors with fires and gas and electrical appliances. There may be inability to handle personal affairs. Personality is involved causing the person to behave differently from her customary pattern. She may become restless or aggressive and this behaviour can be very difficult to control.
Verbal communication often is affected, either because the person cannot put her thoughts together in a meaningful way, or because she can no longer coordinate the muscles of the face and throat in order to produce intelligible speech.
Care Needs
The first need of a dementing person is for supervision because of the loss of short-term memory. She may be unsafe cooking, not because she is unaware of the dangers involved, but because she forgets them. For example, she may forget that the gas is turned on but not lit. If reminded about it she will immediately appreciate the potential danger involved.
As the condition develops the person may need help at the beginning and end of the day with dressing and washing. The progressive decline in ability to care for herself will reach a point at which the person is in significant danger from accident or neglect. At this point she is no longer aware of dangers.
In the later stages of the disease there is a significant deterioration in physical ability as well as mental. Supervision alone will not then suffice; there is an increasing need for attention in connection with bodily functions.
The fact that a person with dementia requires supervision through the day does not mean that watching over is also required at night. Many demented people sleep undisturbed throughout the night. Even if the person does waken, she will often remain quietly in his bedroom in no danger. Others will wander and be at risk, particularly if they have other problems that put them in danger of falling. These people will need watching over.
Incontinence, commonly of urine, less commonly of faeces complicates many cases of dementia in time. It is often concealed by the person and by their carer because of embarrassment. This may add considerably to care needs.
Mobility Considerations.
A dementing person may be unable to get about out of doors because of loss of short-term memory: She may need guidance because she cannot remember where she is going.
Physical deterioration in the late stages of the disease may also have a significant effect on the person's walking ability, and may in fact be so severe that the person becomes totally chair-or bed-bound.
Duration of Need.
Dementia is a progressive condition and the needs of the affected person are likely to increase throughout the remainder of her life.
Damage to the brain such as a head injury or encephalitis (inflammation of the brain) may produce the clinical picture of dementia except that it may not be progressive. The disability resulting from this is the same as for dementia due to other causes. There is, however, some room for improvement over a period of a year or so. If after this period there has been no improvement the disability is then likely to be permanent.
Further Evidence.
In moderate or severe cases of dementia the situation is usually readily apparent and the care and mobility needs are easily determined. However, general statements about risks to the demented population as a whole are not helpful. Of much greater importance is any specific evidence on care and mobility needs related to the individual person.
In less severe cases the presence of dementia may be overlooked, a person's unusual behaviour being attributed to other causes. The sufferer herself, lacking insight into her condition, may deny that she is unable to do things and give a false and over optimistic picture of her capabilities. In all cases in which dementia is suspected, evidence from the person caring for the disabled person is very helpful in getting a full and accurate picture of the overall disability. If there is no-one caring for the person then a report from a GP may help. Alternative sources of information are the local authority social services or hospital geriatric department.
The Effects of Age.
Because dementia mainly affects older people, physical disabilities are frequently present as well. The person may be less able to cope with these because of her mental state. The total needs because of the combination of physical and mental disability should be taken into account.
