IT’S A MYSTERY!

Health questions that have perplexed the experts

This week: What causes dementia?

THE lack of treatments for dementia is partly because scientists are still pinning down why and how it happens.

In Alzheimer’s disease, the most common type of dementia, proteins called amyloid and tau build up in the brain and are thought to cause such symptoms as impaired memory and confusion.

Simon Ridley, head of research at Alzheimer’s Research UK, says: ‘We know these proteins build up and kill nerve cells, but don’t understand why. Though age is the biggest risk factor for most cases of dementia, we don’t understand why some people get it and some the same age don’t.’

MRI scans have shown that people can have these proteins, but not suffer symptoms. ‘It may be those people are delaying their susceptibility,’ says Mr Ridley. ‘If we could all delay our susceptibility by 20 years, that would help a lot of people.’