Question

What is the difference between Alzheimer's and other types of dementia?

Answer

Dementia is the term used for chronic generalised psychological impairment. The main clinical feature is generalised intellectual impairment but there are also changes in mood and behaviour. The underlying brain dysfunction is generalised. Having said that, dementia is just a description of how the patient presents to the doctor, and there are many different conditions which cause. There are some dementias which are classifiable during life, but most of them are (usually correct) best guesses, because clearly one cannot biopsy the brain of a living person to be absolutely sure.

An expert opinion can help to rule out the treatable causes of dementia and can provide advice on how to manage the individual, particularly as the condition progresses.

Whether a condition progresses or not depends on the underlying cause of the dementia. Alzheimer's disease is one form of dementia, and is due to a biochemical abnormality. There is some hope that a treatment for this will emerge in the future. It is probably as common as dementia secondary to hardening of the arteries, which is called multi-infarct dementia, or vascular dementia. In this, the blood supply to the brain has been interrupted (e.g. through a stroke) and small areas of the brain have died. Although these are the two most common types of dementia, there are other causes, which include Huntingdon's chorea, Parkinson's disease, normal pressure hydrocephalus, tumours and subdural haematomas, head infection, metabolic causes, toxic causes and even some cases of vitamin lack. The prognosis and the type of symptoms depend on the type of dementia and its severity.