Brain Health

New Blood Test for Alzheimer's Needs Less Sample and Beats PET Scan Accuracy

Researchers at the University of Pittsburgh developed a faster, cheaper blood test for early Alzheimer's disease detection. The improved immunoprecipitation-mass spectrometry assay measures amyloid-beta peptides in plasma using 75% less antibody and far smaller blood samples than before. In 317 cognitively normal older adults, the new test's amyloid-beta ratio achieved an AUC of 0.81 in detecting abnormal brain amyloid scans — significantly better than the 0.65 achieved by the older method. The test worked reliably with as little as 100 microliters of blood. This advance could make early Alzheimer's screening accessible in routine clinical settings and community research studies without requiring expensive brain imaging or spinal fluid draws.