New dementia classification for disease with Alzheimer’s like symptoms
30 April 2019
Brain: Limbic-predominant age-related TDP-43 encephalopathy (LATE): consensus working group report.
Researchers in the US have reviewed the latest evidence that a protein TDP-43 is implicated in a new disease process called Limbic-predominant age-related TDP-43 encephalopathy (LATE). The findings are published today (Tuesday 30 April) in the scientific journal, Brain.
Dementia is a complex condition caused by a number of progressive brain diseases of which Alzheimer’s, while most common, is just one type.
The diseases that cause dementia usually involve a build-up of proteins inside the brain. While all of these diseases cause damage to nerve cells, they can be distinguished by which proteins they involve and by which areas of the brain that they affect.
This new review of studies focuses on a protein called TDP-43 in brain tissue of people with dementia. TDP-43 has already been identified as a cause of frontotemporal dementia, a condition that leads to personality changes and communication difficulties.
This analysis suggests that a build-up of TDP-43 in an area of the brain called the limbic system is associated with the memory-related symptoms that are typical of Alzheimer’s disease.
Dr Carol Routledge, Director of Research from Alzheimer’s Research UK, said:
“While the research indicates that LATE could be contributing to damage to the brain in around 17% of older people diagnosed with Alzheimer’s, this isn’t yet something doctors will be able to diagnose in the clinic.
“People are diagnosed with a specific form of dementia based on the symptoms they experience. When the symptoms of diseases overlap, it is very difficult to reliably determine the underlying cause.
“Although we tend to look at the brain changes that cause dementia as separate diseases, multiple processes are often underway at the same time. It can be difficult to say where one disease starts and the next one stops. As we learn more about the complex brain changes involved in dementia, it’s not surprising that new subtypes of diseases could emerge.
“Alzheimer’s Research UK is investing in research into a number of culprit proteins implicated in dementia including TDP-43. To have the best chance of developing effective treatments, we have to improve the diagnosis of specific causes of dementia and develop targeted drugs that can be tested in the right patients at the right time.”