Blood Test For Alzheimer's Available Soon

Canadian researchers have raised new hope for early diagnosis of Alzheimer's disease, with a simple blood test they say will soon be commercially available.

Researchers at McGill University Health Center (MUHC) in Montreal have published their findings in the latest issue of the Journal of Alzheimer's Disease.

"Until now, there has been no definitive diagnostic tool for Alzheimer's, other than postmortem analysis of brain tissue," said senior author Dr. Vassilios Papadopoulos, director of the MUHC Research Institute. "Our clinical study shows that a non-invasive blood test, based on a biochemical process, may be successfully used to diagnose Alzheimer's at an early stage and differentiate it from other types of dementia."

The brain produces a hormone called dehydroepiandrosterone, or DHEA. The hormone is produced at high levels.

How the test works

The researchers found that, with a certain test, they could promote the production of DHEA in a blood sample. In the blood sample of someone who does not have Alzheimer's, that is. If the sample were from an Alzheimer's patient, the test does not result in the creation of the hormone.

Therefore, if the blood test fails to produce DHEA, the patient has Alzheimer's.

"There is a clear correlation between the lack of ability to produce DHEA through oxidation in the blood and the degree of cognitive impairment found in Alzheimer's disease," said Papadopoulos. "We demonstrated we could accurately and repetitively detect Alzheimer's disease, with small samples of blood. This test also allowed for differential diagnosis of early stages of Alzheimer's disease, suggesting this can be used as a test to diagnose the disease in its infancy."

Treatment implications

In recent years other researchers have scored promising results in therapies designed to treat Alzheimer's disease, which robs victims of their memories before it ultimately kills them. With the large Baby Boom population entering their senior years – the time when the disease normally strikes – there has been a concerted effort to find a cure, or at least an effective treatment.

While there are many promising therapies in development, they all depend on the reliability of a diagnosis. Currently the diagnosis of Alzheimer's follows the sequence of family history, information, mental assessment and the physical exam, focusing on neurological signs.

"An accurate, easy and specific non-invasive biochemical test that correlates with clinical findings is vital,” Papadopoulos. We believe our results demonstrate that the DHEA-oxidation blood test can be used to diagnose Alzheimer's at a very early stage and monitor the effect of therapies and the evolution of the disease."

More study

The Alzheimer's Society says, however, DHEA research is in the very early stages and it isn't certain a blood test will be available quite as quickly as the researchers are.

“Much more research is now needed to confirm these findings and better understand whether the DHEA blood test could provide useful information about the diagnosis or progression of Alzheimer's disease,” said Clive Ballard, Director of Research for the Alzheimer's Society.