A New Alzheimer ’s Blood Test Proved 94% Accurate in Finding Brain Changes Related to the Disease

In this study, the team took samples from 158 people over the age of 50, most of whom were cognitively normal at the start of the study, and followed them for about four years to see which participants developed Alzheimer’s. To verify the amyloid levels found in the blood test, the volunteers also had a PET scan of their brains and provided samples of cerebrospinal fluid, near the start and then again near the end of the study period. The blood samples were collected within 18 months of the first amyloid PET scan, and 88% of the time, the blood test matched the scan. That’s not accurate enough to use as a test to identify people at-risk of Alzheimer’s, so the team then combined the blood test with other well-known risk factors, such as the presence of a genetic factor called ApoE4, and age. When these additional factors were considered, the combination matched the PET scan 94% of the time. Previous efforts, including one by a group of Japanese researchers, to develop a blood test have compared the blood results to PET imaging, but for the first time, the Washington University researchers also tracked the blood test and PET scan results over time. They found that people who had negative amyloid PET scans at the start of the study but positive amyloid blood tests had a 15-fold higher risk of having a positive PET scan by the end of the study. In other words, the blood test may be picking up very early changes in amyloid, that weren’t detectable on the br...
Source: TIME: Health - Category: Consumer Health News Authors: Tags: Uncategorized Alzheimer's Brain embargoed study Source Type: news