Simple blood test 90% accurate in predicting Alzheimer's

Oct 15 2007

A new blood test which has been developed by scientists in California may enable doctors to predict just who is likely to develop the the degenerative brain disease Alzheimer's.

The researchers at Stanford University in Palo Alto believe the blood test could possibly provide a simple screening test for Alzheimer's.

Dr. Tony Wyss-Coray, an associate professor of neurology and neurological sciences at Stanford who is the lead author of the study says the test would not only pick up the presence of Alzheimer's, but could also indicate who is likely to develop the condition.

The test identifies changes in some of the proteins in blood plasma that cells use to convey messages to one another.

For the study the research team compared 259 blood plasma samples from clinics in the U.S., Sweden, Poland and Italy; some were from patients with Alzheimer's, and the others were from patients without the disease.

Their simple blood test found there were 18 signaling proteins in the blood plasma and was able to indicate who had Alzheimer's with 90 percent agreement with clinical diagnoses, and could predict the onset of Alzheimer's two to six years before symptoms appeared.

The researchers say by taking a sample of blood and examining the proteins in the plasma, a doctor is almost 'listening to the language of cells' and may see if a disease process is going is underway.

Dr. Wyss-Coray says though the test will not be available for a few years, he is excited about its implications.

Other experts too are optimistic. and say the results are more significant, and success rates are better than other potential tests and agree there is an urgent need for better tests for Alzheimer's disease.

One of the most distressing aspects of Alzheimer's disease is the difficulty in determining whether mild memory problems are the beginning of an inevitable mental decline.

Current methods for diagnosing Alzheimer's rely on excluding other possible causes of memory loss and cognitive declines, such as stroke, tumors and alcoholism.

Alzheimer's is the most common cause of dementia and the only definitive diagnosis is by brain autopsy after a person has died.

According to the Alzheimer's Association, more than 5 million Americans are victims of the disease, which destroys patients' memory, thinking and the ability to communicate.

The researchers say their findings show that it is possible to use factors in the blood to diagnose and even predict the disease, but they also say the findings must now be confirmed by other laboratories.

The study was supported by the John Douglas French Alzheimer's Foundation, the Alzheimer's Association, the U.S. National Institute of Aging and Satoris Inc. and is published in the current issue of the journal Nature Medicine.