Measuring blood levels of P-tau181 may allow doctors to diagnose Alzheimer's before the onset of symptoms. Elevated levels of P-tau181 in the blood were associated with greater amyloid beta accumulation in the brain and outperformed two other biomarkers in predicting signs of amyloid beta in brain scans.
A newly developed blood test for Alzheimer's disease measures a specific variant of the tau protein. Early results show the test has a good capacity to distinguish Alzheimer's disease from other tauopathies.