Blood test for Alzheimer's

Blood test may diagnose Alzheimer's, study suggests.

"There is important news to report tonight in the fight against Alzheimer's disease. Researchers are reporting major progress toward a simple blood test that could detect the disease earlier than ever before." According to findings published in the journal Nature Medicine, "doctors may be able to predict if mild memory loss is a warning sign of the disease."

Stanford University researchers "developed a test that was about 90 percent accurate in distinguishing the blood of people with Alzheimer's from the blood of those without the disease." Furthermore, the test "was about 80 percent accurate in predicting which patients" with mild cognitive impairment "would go on to develop Alzheimer's disease two to six years later."

While experts hailed the results as promising, they "cautioned that the work needed to be validated by others and in much larger studies, because there have been many disappointments in the past."

Tony Wyss-Coray, M.S., Ph.D., and colleagues, "tested blood from 259 patients with early-to-late-stage Alzheimer's, along with another group of people without the disease. They found levels of 18 protein messengers varied in patients compared with healthy people."

"The test initially will be used in research labs, where scientists are trying to learn more about the memory-wasting disease that is one of the most feared consequences of aging." The test will not be available commercially for at least two more years, during which time additional studies will occur.

Currently, about "4.5 million people in the United States" have Alzheimer's disease.