A groundbreaking discovery by an international team of doctors and researchers is set to completely overhaul the way that we view dementia.
A new report published this week in the online journal Brain– A Journal of Neurology outlines the discovery of a new condition of dementia that is being called LATE.
The term LATE stands for ‘limbic-predominant age-related TDP-43 encephalopathy’ which basically refers to the area of the brain most likely to be affected, and the protein that is thought to be the predominant cause of the condition.
It has been revealed that LATE often mimics many of the same symptoms as Alzheimer’s disease, and the study also indicates that between 20 and 50% of people who are over the age of 80 will have brain changes associated with the LATE condition.
Doctors also believe that LATE may be more common than Alzheimer’s disease amongst the oldest adults.
Honorary Medical Advisor at Dementia Australia and Associate Professor Michael Woodward, AM, sat down with HelloCare to shed some light on the new discovery.
“We don’t know exactly how many people are affected, it could be as much as 20% or 30% in people over the age of 80 but that’s yet to be properly defined,” said Professor Woodward.
“However, there is certainly a significant amount of older people who appear to have Alzheimer’s disease clinically, but when you look at their brains at autopsy, they don’t show the pathology of Alzheimer’s, and some of these people certainly do have this condition called LATE.”
The similarities in the symptoms of both LATE and Alzheimer’s disease have forced medical professionals to rethink how they approach Alzheimer’s treatment – people who had previously been diagnosed with Alzheimer’s but saw no positive benefits from Alzheimer’s treatments may actually have been living with the LATE condition instead.
And just to make things even more confusing, doctors also believe that both LATE and Alzheimer’s are often found together.
“Unfortunately, where things get very problematic is the fact that the symptoms for both LATE and Alzheimers can be so similar. There might be one exception though, which may be that the LATE condition can progress very slowly,” said Professor Woodward.
“There is a group of people who have significant memory problems after the age of 80, and when you look at their brain after they pass away, they don’t have Alzheimer’s – now why is that important? The truth is that the treatments that we have for Alzheimer’s have only been shown to work for Alzheimer’s”
“If we are going to do research on drugs that target the protein ‘amyloid,’ which we think is the main cause of Alzheimer’s, we are not going to have much success if we include people that have the LATE condition, because the cause of LATE is related to a separate protein known as TDP-43.”
Proteins within the human brain have long been thought to be one of the root causes of different types of dementia, as certain proteins create protein tangles inside brain cells that can affect the way that the cells can communicate with other brain cells – which eventually leads to the death of brain cells.
According to Professor Woodward, while the protein TDP-43 is seen as one of the most specific causes of the LATE condition, it is was discovered years ago as a contributing factor to another form of dementia.
“TDP-43 was first discovered by a researcher by the name of Ian Mackenzie, and he worked in Melbourne alongside Colin Masters who was one of the first people to characterise the Alzheimer’s protein amyloid, and he has shown very eloquently, that TDP-43 causes quite a few forms of dementia,” said Professor Woodward
“He was initially looking for TDP-43 in another group of dementia’s known as Frontotemporal dementia, and he found it, but we now really need to investigate how much TDP-43 is associated with this condition LATE.”
As expected with such a new discovery, treatment for people living with the LATE condition does not yet exist, but Professor Woodward did say that the discovery of LATE would ‘definitely’ have a positive effect on all forms of current dementia research.
“At the moment there is no treatment that is effective treatment for LATE, in fact, there’s not really that many effective treatments for Alzheimer’s disease, it would be fair to say that we need to develop better treatments for Alzheimer’s, but we also need to better identify and develop treatments for LATE,” said Professor Woodward.
“It’s a bit like cancer, we don’t have a drug that cures cancer, we have that drug that cures breast cancer or a drug that cures prostate cancer, and in the same way, it’s probably unfair to say that we are going to get a drug that helps to treat or cure all dementia. We need a drug that cures Alzheimer’s, we need a drug that cures LATE, and we need drugs that cure other forms of dementia.”
While any new discovery regarding dementia is a positive step towards the prospect of hopefully finding an effective treatment or cure, Professor Woodward did have some sobering words for those with a current Alzheimer’s diagnosis who are thinking that they may actually have the LATE condition instead.
“We don’t actually want people who have been told that they have Alzheimer’s to think ‘oh hang on, maybe I don’t have Alzheimer’s,’ and think that it’s not that big of an issue, we need people to understand that any form of dementia has significant issues, and it might be nice to know that there are other forms of dementia other than Alzheimer’s that can cause similar symptoms, but that is no reason to not take an Alzheimer’s diagnosis lightly.”
