What is dementia?

Doctors use the word dementia to describe the gradual deterioration of a person's mental abilities, in combination with changes in personality and behaviour. It is rarely seen in people under the age of 70.

What are the symptoms?

The main symptoms of dementia include memory loss, disorientation, communication difficulties, personality changes (moodiness and bad temper are quite common) and a gradual decline in the person's ability to undertake ordinary, everyday activities.

Memory loss is often the first clear symptom, and memory of recent events tends to decline more quickly than the person's ability to recall long-term memories. Disorientation is also common. This is where the person begins to lose all sense of time and place. This may, for example, make them reluctant to leave the house, as this can be terrifying to the sufferer.

Dramatic changes in the sufferer's personality are common but by no means universal. Social withdrawal and a marked loss of interest in usual routines and activities are commonly observed. More distressingly for family or carers can be the sudden mood swings and the development of quite unpleasant personality traits, such as spitefulness or the use of foul language. At more advanced stages in the disease, the person's behaviour may have deteriorated almost entirely to a level that would be socially unacceptable.

In combination with this is a gradual decline in practical skills, such as cooking, opening a tin of food or driving. As the disease advances, even the most basic skills, such as dressing or washing, may also be lost. Verbal ability also declines sharply; conversations become disjoint and reading and writing become increasingly difficult for the person.

What causes dementia?

The term dementia is not really regarded as a complete medical diagnosis. There are a number of individual diseases which can produce the symptoms of dementia, so the doctor will attempt to identify which is the likely culprit before deciding on a course of treatment or management. According to the Alzheimer Society of Ireland, it is estimated that 33,000 people in the Republic of Ireland have dementia, most of whom have Alzheimer's Disease which is the most common cause of dementia and represents about 60% of all cases. Alzheimer's is a progressive degenerative disease which gradually kills brain cells.

A small number of Alzheimer's cases are believed to be as a result of a defective gene, but in most instances the cause of the disease is unknown. Other possible causes of dementia include stroke or vascular dementia, the long term effects of repeated head injury (as in former boxers), vitamin B12 deficiency, an under-active thyroid or drug interactions - these always have to be reviewed in the elderly, who may be on several medications as the same time. For more information on Alzheimer-related dementia, contact the Alzheimer Society of Ireland on 1800 341 341 or online at

Can dementia be cured?

Unfortunately, this is very much as progressive disease. However, it is vital that the person is fully medically reviewed, as other conditions such as depression in the elderly (which responds well to treatment) may mimic the symptoms of dementia. Also, some forms of dementia, although incurable, do respond well to medication, which may slow up the rate of decline and improve the person's quality of life. Your GP is your first line for advice

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