A Blood Test That Could Diagnose Alzheimer's Shows Promise.

In what might prove to be an important advance in getting treatment to Alzheimer's patients as early as possible, UCLA researchers have found that a simple blood test might be developed that could diagnose patients with Alzheimer's.

While there is currently no cure for Alzheimer's, getting treatment to patients as early as possible is important, as many treatments are most effective in the earliest stages of the disease.

At present, the only way to definitely prove the presence of Alzheimer’s is through the examination of brain tissue after death, however, to diagnose patients while they are alive, doctors rely on the presence of biomarkers (beta amyloid proteins in the brain, a hallmark of the disease) and cognitive symptoms such as memory loss.

Two methods are currently used to determine the beta-amyloid formation characteristic of Alzheimer’s disease, however, there are significant drawbacks to both. A spinal tap can be used to obtain cerebrospinal fluid, however, this is an invasive procedure that carries the risk of nerve damage and other serious side effects. Alternatively, an amyloid PET scan can be used, and while this technology is non-invasive, it exposes subjects to radiation. Moreover, amyloid PET scans are available in only few medical centers, and are not typically covered by insurance as a diagnostic test. 

For their study, the UCLA researchers developed a simple signature for predicting the presence of brain amyloidosis — the build-up of amyloid in the brain — including several blood proteins known to be associated with Alzheimer’s disease, along with information routinely obtained in the course of a clinical work-up for patients suspected to have the disease, such as results of memory testing and structural magnetic resonance imaging.

The UCLA researchers found that their method could be used to predict the presence of amyloid in the brain with modest accuracy.

"Our study suggests that blood protein panels can be used to establish the presence of Alzheimer’s-type pathology of the brain in a safe and minimally invasive manner,” said Liana Apostolova, MD, director of the neuroimaging laboratory at the Mary S. Easton Center for Alzheimer’s Disease Research at UCLA and head of the research team. “We need to further refine and improve on the power of this signature by introducing new disease-related metrics, but this indicates that such a test is feasible and could be on the market before long.”

Results of the study appeared in the journal Neurology.