The main causes of dementia

If you or a loved one has been diagnosed with dementia you’ll probably want to understand what might have caused it. Here’s where it all starts…

In a nutshell

Dementia is caused by damage in the brain, which makes the brain cells degenerate and die more quickly than they would normally. This damage can lead to problems with memory, changes in personality and general difficulties with everyday living.

Three facts worth knowing

1. The most common cause of the brain damage that leads to dementia are neurodegenerative diseases, such as Alzheimer’s, dementia with Lewy bodies and frontotemporal dementia (sometimes called Pick’s disease).

2. A restriction in blood supply to the brain can also cause the brain damage that leads to dementia. This is called vascular dementia.

3. There are other less common causes of dementia or dementia-like symptoms too, such as head injuries, alcohol misuse, lack of vitamin B, and depression (though some of these are treatable and can even be reversed).


What actually happens

Exactly how dementia progresses will differ from person to person and can depend largely on the type of dementia you are diagnosed with. The most notable symptom of many types of dementia – particularly Alzheimer’s – is memory loss, however this isn’t always the case. For example, a person with frontotemporal dementia may not have too much difficulty remembering things but may seem cold and withdrawn or behave in a way that seems out of character. In most cases dementia symptoms will get worse but don’t panic because this can take a long time – and there are lots of ways to manage the symptoms and continue to live well.

Here’s the science

A build-up of abnormal proteins in the brain is to blame for most types of neurodegenerative dementia (such as Alzheimer’s and dementia with Lewy bodies). In Alzheimer’s these proteins are called ‘plaques and tangles.’ In dementia with Lewy bodies and frontotemporal dementia (Pick’s disease) the proteins are called ‘Lewy bodies’ and ‘Pick bodies’ after the scientists who first discovered them both.

Vascular dementia however is caused, not by abnormal proteins, but by a restriction in blood flow to the brain, usually in the form of a stroke.


The good news

Research into what is happening in the brains and nerve cells of people with dementia is growing rapidly. Scientists are confident that a drug to significantly slow the progress of the most common types of dementia – or even cure them – will be available within ten years.