Intro: Big news in Alzheimer’s research: the FDA has just cleared a new blood test from Roche Diagnostics that may help primary care providers screen for Alzheimer’s disease earlier and less invasively than ever before. The Elecsys pTau-181 Blood Test Roche’s Elecsys pTau-181 test measures a specific protein, phosphorylated tau (pTau-181), in the blood. Elevated levels of this protein are associated with Alzheimer’s-related brain changes. Until now, Alzheimer’s biomarkers we