Family doctor

What is it?

Dementia is defined as an acquired, usually persistent impairment of intellectual function, including memory problems and at least one of the following - language impairment, visuospatial (orientation) problems, difficulties with calculations, reasoning, and abstraction. Personality change may occur. Despite these impairments, the person remains fully alert. However, these intellectual losses are severe enough to interfere with work or social activities.

Dementia is a syndrome and as such does not refer to a specific disease. There are a large number of causes. The more important causes include:

• Alzheimer's disease
• Multiple strokes ("vascular dementia")
• Alcohol
• Head injuries
• Brain tumours
• Hydrocephalus (water on the brain)
• Parkinson's disease (but not all patents with Parkinson's disease get dementia)
• Infections such as meningitis, AIDS and certain viruses
• Vitamin deficiencies (especially Vitamin B12)
• Hormonal disturbance such as an under-active thyroid gland

*The first two causes account for the majority of cases.

Dementia becomes more common with age. Five percent of the population over 60 are said to have dementia, but this rises to 20% of the population over 80 years. It appears to affect all ethnic groups. It is a common cause of disability in the elderly, and is common in residents of rest homes and geriatric hospitals.

What are the symptoms?

The changes tend to be slowly progressive, and subtle at first. It is common to notice memory problems initially. However, this needs to be distinguished from mild memory loss that occurs with age and is not related to dementia. Often the changes are noticed first by family and friends, rather that the patient.

With time, the initial memory loss becomes more severe and obvious. Long term and short term memory becomes affected. Other intellectual functions become affected. The person may have difficulty in balancing their chequebook, difficulty counting change, may show poor judgement with purchases, and their self-hygiene may decline. A personality change may occur with the person becoming more slovenly, rude, and sometimes uninhibited. All these symptoms occur at different rates and to different degrees, depending on the underlying cause.

Dementia needs to be distinguished from:

• Delirium, a temporary condition of brain dysfunction, associated with disturbed consciousness, which typically fluctuates. It is usually caused by some physical illness.
• Depression
• Strokes which may, for example, produce speech difficulties without dementia
• Sensory impairment, such as severe deafness

It is important for people with suspected dementia to see a physician, so that the diagnosis can be confirmed, the cause can be determined, and so that treatment can begin.

What tests are needed?

Usually a clinical assessment is needed, a few blood tests and a brain scan. Sometimes neuropsychological tests, including various "puzzles" are performed to determine which part of the brain is most affected. Occasionally other tests such as analysis of spinal fluid and electroencephalograms (brain wave measurement) are required.

What can be done to help?

Treatment depends on the cause. In some circumstances, treatment of the underlying cause results in a considerable intellectual improvement. However, in the majority of cases, dementia is persistent and often gets worse (progressive).

It is important for sufferers of dementia to be well informed regarding their diagnosis and prognosis, so that they can anticipate the future. They require advice on wills, appointing Powers of Attorney, financial planning etc. It is important to provide support for their caregivers, such as relief care. Maintaining a familiar environment and routine is helpful and avoids episodes of acute confusion. Unnecessary medications should be withdrawn (under the supervision of a physician).

Specific remedies depend on the cause. In certain cases, drugs are beneficial. Depending on the cause, other interventions may help. For example, cessation of alcohol in alcoholics; surgery in hydrocephalus; control of blood pressure and aspirin in vascular dementia; certain drugs in Alzheimer's disease. Behavioural symptoms often respond to non-pharmacological interventions. Recognising patterns of behaviour, and avoiding precipitants of undesirable behaviour (which are often recognised in time), and behaviour management strategies are helpful.

Future trends

A vast amount of research is continuing into dementia. New discoveries are being made regularly. For example, new drugs have recently become available for the treatment of Alzheimer's Disease.

There is growing confidence that in the future, our ability to prevent and treat dementia will improve greatly.

Getting help

All patients with suspected dementia should have an assessment by a physician. Specialists who may be asked to see the patient include neurologists, gerontologists (geriatricians), and neuropsychologists. Physical therapists (physiotherapists) and occupational therapists also have an important role in assessment and treatment. Your local Assessment Treatment and Rehabilitation Unit (Geriatric Unit) can often provide comprehensive assessments.

A number of support organisations are available. In New Zealand, the Alzheimer's Foundation (phone 09-6255280) is a useful source of information and support. They have a library of information, as well as a 24-hour telephone information line (09-6255678). The Health Funding Authority of New Zealand funds courses on dementia for caregivers.