What are the dementias and common misconceptions?

Dementia is one of those words that is really misused.

It is seen, I think, in the media and often in public perception as something that only affects elderly people. And while it is now the most feared condition, having overtaken cancer as the medical condition most feared by people over the age of 40 in the UK, it still has a connotation of just being forgetfulness, a horrible, sad condition. It’s a gradual decline, but it’s something that affects elderly people, and they’ll eventually just lose abilities. The reality of dementia is that it is much more complex and nuanced than that. In fact, dementia should be considered as a very broad umbrella term. It just means the loss of cognitive– of brain– function. It’s no more specific than saying skin failure.

And as such, we wouldn’t accept, if we went to see a doctor and said that I think I’ve got this thing wrong with my skin, I’ve got this rash here, to be told, oh, well, that’s just a rash. Dementia is a syndrome. It has many causes. We should not be diagnosing dementia. We should be diagnosing the cause of dementia in the same way that every cancer has a type, a stage. Every dementia has a cause, the most common being Alzheimer’s disease. Vascular dementia is common, a problem with the blood supply. But there are many other causes too.

So we have forms of Alzheimer’s disease which may present with visual problems affecting the back of the brain, which is called posterior cortical atrophy or PCA. We have language presentations, which present with progressive deterioration in ability to speak and to communicate, and aphasia, so-called primary progressive aphasia or PPA, language-led dementias. And we have behavioural frontal forms where, actually, it’s not memory but it may be changes in behaviour that can easily be missed for just people being, inverted commas, difficult or changing or things that are often hard to put a finger on. And those frontal conditions are often caused by something called frontotemporal dementia, FTD.

But in addition, there are overlaps between some of the problems in the brain that cause movement problems and some of the ones that cause thinking. So dementia with Lewy bodies has some elements of Parkinson’s disease and some elements of the cognitive problems that we get in Alzheimer’s disease. And there may be quite unusual features that people have trouble understanding– visual hallucinations, great fluctuations. So people may seem relatively OK one moment and then very confused another. Many of these problems, whether it’s PCA, FTD, inherited familial Alzheimer’s disease, dementia with Lewy bodies, DLB, bring additional burdens, but they also bring a delay in diagnosis because they don’t fit the standard doctors’ or public’s perception. That’s very hard for people with those conditions.

It’s hard for their families.