“The researchers gathered more than 200 blood samples from people with Alzheimer’s and those without. Using 83 of the samples, they measured the abundance of 120 proteins involved in cell signaling and found they could distinguish the Alzheimer’s samples from the controls using 18 of the proteins.

They then tested their 18-protein signature on an additional 92 samples. The tests agreed with the clinical diagnosis about 90 percent of the time.

Perhaps most intriguing were the results of the test on 47 blood samples taken from people with mild cognitive impairment, a minor loss of memory that can be a precursor of Alzheimer’s. The test was able to predict with about 80 percent accuracy whether a patient went on to develop Alzheimer’s two to six years after the blood sample had been collected.” (New York Times )