Blood Sample Test Can Predict Alzheimer's Disease

Alzheimer’s disease may be able to be detected 10 years before onset via a blood test, according to a report published by Bloomberg News.

Researchers from the National Institute on Aging evaluated 174 patients with 100 percent accuracy using the new test as either Alzheimer’s disease or healthy. The California based company that created the test, NanoSomiX, said they plan to create a commercialized version of the test. The research was presented at the Society for Neuroscience conference in Washington in November.

The test works by identifying a brain protein that is involved in insulin signaling, called IRS-1, which is an early predictor that is defective in Alzheimer’s disease patients.

The investigators sampled each patient’s blood: 70 of which had Alzheimer’s disease, 20 cognitively elderly patients with diabetes, and 84 healthy adults. From the Alzheimer’s disease group, 22 patients’ blood samples were used from blood samples taken 1-10 years prior to diagnosis.

Exosomes were isolated from the blood samples, and the ones that originated in the brain were identified by the test, including IRS-1. Then, protein levels were measured. From that data, the researchers extrapolated Alzheimer’s disease patients had higher amounts of inactive protein and lower amounts of active protein than the healthy individuals. The diabetic patients had intermediate levels of each.

The results were consistent each time, including with the samples taken 1-10 years prior to Alzheimer’s diagnosis. The test was able to predict what patient group the blood samples came from without errors, as well.

“We will need replication and validation, but I’m very optimistic this work will hold,” the study’s lead author Dimitrios Kapogiannis, MD, described to Bloomberg. “We were able to perfectly classify patients and controls.”

Other tests designed to identify Alzheimer’s disease were announced earlier this year, the Bloomberg article noted. The first works by measuring 10 fats in the bloodstream that have appeared to predict dementia within 3 years of onset with about 90 percent accuracy. The other analyzes 10 proteins in the blood to predict onset with 87 percent accuracy within a year.