Overview
- Researchers reported Tuesday that a plasma pTau217 blood test forecast who would later show amyloid on brain scans and who would experience cognitive decline.
- Each one‑point rise in baseline pTau217 was linked to about 0.35 centiloid units more amyloid per year on PET, while very low levels signaled little near‑term buildup on this standardized plaque scale.
- The Nature Communications paper followed 317 cognitively unimpaired adults in the Harvard Aging Brain Study for roughly six to eight years with repeat PET scans and long‑term memory testing.
- The test uses a mass‑spectrometry measure of percent pTau217 from a standard blood draw, offering a cheaper, less invasive option than PET scans or spinal taps for identifying higher‑risk people.
- The findings support trial recruitment and earlier risk stratification, though experts caution that routine screening of healthy adults is not advised yet and note assay standardization needs and disclosed ties to C2N Diagnostics, with primary funding from the National Institute on Aging.