When There's No Amyloid, It’s Not Alzheimer’s

This is the heading to a fascinating article in the latest Alzforum weekly newsletter. Here's a link to the article:

http://www.alzforum.org/news/research-news/when-theres-no-amyloid-its-not-alzheimers?utm_source=Alzforum+Weekly+Newsletter&utm_campaign=0372e368ea-September_14_2015_Newsletter&utm_medium=email&utm_term=0_944a562dd7-0372e368ea-91738709

And the first paragraph gives you the gist:

Reporting in the August 24 JAMA Neurology online, researchers led by Eric Reiman at Banner Health in Phoenix, confirm what others have suspected from PET imaging, namely, that as many as one-third of the people clinically diagnosed with mild to moderate Alzheimer's disease do not meet criteria for significant amyloid accumulation in the cerebral cortex. Reiman and colleagues came to this conclusion after examining brain tissue postmortem—the gold standard for assessing amyloid burden. The finding puts the kibosh on the idea that some PET scans are negative because amyloid ligands bind poorly to particular forms of amyloid in some AD patients. It also reinforces questions about the accuracy of clinical diagnoses of AD and leaves the field struggling to explain what causes dementia in these amyloid-negative individuals. This promises to be an intense area of investigation, said Reiman.

Articles like these are often difficult for a lay person to understand. But from what I can understand and already know I would say the title is begging the question a tad. It should be no surprise that many people diagnosed with AD are found post mortem not to have amyloid accumulation in their brains. But surely this could be because either, as the title says, people without the amyloid must have a different disease or different diseases OR because, as other research suggests, amyloid accumulation is not as significant in AD as is so often claimed.

Paying GPs £55 for diagnosing dementia

Readers in other countries may not be aware of a news story that is currently causing some controversy in the UK,  There is a proposal that GPs should be paid £55 for every case of dementia they diagnose (as I understand it, the money would go to the practice rather than to the GP personally).

Amongst the points that have been raised:

* Why should anyone be paid more for simply doing their job which diagnosis is part of?

* In reality when GPs suspect that a patient may have dementia they will normally refer them to a memory clinic/service for tests and scans and, hopefully, a confident diagnosis.

* There is anecdotal evidence that some GPs fail to spot the signs of dementia, particularly in younger people and, certainly, it would be unwise to assume that a GP can make an accurate diagnosis of the condition.  I've read of two cases recently where people have been wrongly diagnosed as having dementia.  In one case, a woman sold her house to pay for care and spent over a year in a care home before the error was discovered.

* A distinction needs to be made between a diagnosis of the condition we call dementia and a diagnosis of one or more of the diseases that cause the condition. If it's clear that the diagnosis of dementia is not always easy, diagnosis of the disease(s) can be very difficult. It is true to say that a definite diagnosis can only be made post mortem  -  if then.

* Is it wise to rush to diagnose people with a condition for which there is no cure and for which the only treatments are, for many people, inadequate or worse?
I've discussed this in earlier posts which you can find by using the search box (top left).

* Many people living with dementia, and their carers, feel that adequate support post-diagnosis should be the number one priority.  There's also a fear that a rapid increase in the number of diagnoses made will simply put more pressure on support services which are, in many cases, already falling apart or non-existent.