The quest for early and accurate diagnosis of Alzheimer's disease has taken a significant leap forward with the advent of a new blood testing technology.

This breakthrough could revolutionise the way we approach one of the most common and debilitating forms of dementia, offering hope for earlier intervention and better management of the condition.



Alzheimer's disease, which affects up to one in 10 Australians over 65 years of age, is the most prevalent form of dementia, characterised by progressive memory loss and cognitive decline.

Traditionally, diagnosing Alzheimer's has been a complex process involving a combination of medical history, cognitive testing, and, in some cases, more invasive procedures like spinal taps or brain scans.


However, a study conducted in Sweden between February 2020 and January 2024, involving 1,213 patients, has demonstrated that a simple blood test focusing on a form of a protein called tau can diagnose Alzheimer's with a remarkable 91 per cent accuracy.

This new blood test outperforms initial diagnoses made by primary care doctors, which were found to be 61 per cent accurate, and even those made by specialists, which were found to be 73 per cent accurate.

The study, published by researchers from Lund University, highlights the potential of this test to become a standard tool in the diagnostic process for Alzheimer's disease.

'Not too long ago measuring pathology in the brain of a living human was considered just impossible,' Dr Jason Karlawish, a co-director of the Penn Memory Center at the University of Pennsylvania who was not involved in the research, said.



The blood test works by measuring levels of a specific form of tau protein that correlates with the amount of amyloid plaque buildup in the brain.

Amyloid and tau proteins are believed to play a crucial role in the development of Alzheimer's, with abnormal accumulations leading to neuron death and impaired brain function.

A high level of this tau form in the blood indicates a strong likelihood of Alzheimer's, while a low level suggests that memory loss may have a different cause.

Dr Suzanne Schindler, a neurologist at Washington University in St. Louis, United States, explained that the presence of these proteins can be indicative of the disease long before symptoms manifest.

However, experts cautioned that the blood test should be used judiciously, primarily by medical professionals and researchers, and not made widely available to the public.

This is because amyloid buildup can begin up to two decades before memory problems become apparent, and currently, there are no proven preventive measures beyond general health advice.

The Alzheimer's Association is actively working on guidelines for using this blood test, and several companies are expected to seek approval, which will further clarify its appropriate application.

It's important to note that the test is not intended for individuals without symptoms, except as part of research study enrollment.



While there is no cure for Alzheimer's, new drugs are in development. However, treatments like donanemab and Leqembi, which target amyloid proteins, have shown only marginal success in slowing disease progression and come with significant risks, such as brain bleeding and swelling.

The introduction of this blood test marks a significant step in the fight against Alzheimer's, offering a less invasive, more accurate, and potentially faster method for diagnosis.

This development could change the landscape of dementia care, allowing for earlier detection and more tailored treatment plans.
Have you or a loved one faced the challenge of diagnosing Alzheimer's? What impact could this blood test have on your approach to health and well-being? Let us know in the comments below.