Blood p-tau217 levels signal cognitive impairment risk years before symptoms emerge

A six-cohort analysis links higher baseline p-tau217 to rising 5- and 10-year risks, bringing presymptomatic risk models closer while showing why routine screening is not yet ready.

Study: Prognostic Value of Blood-Based P-Tau217 Levels for Progression to Cognitive Impairment. Image Credit: Lightspring / Shutterstock

In a recent study published in the Journal of the American Medical Association, researchers found that baseline concentrations of a blood-based protein biomarker, plasma phosphorylated tau 217 (p-tau217), were associated with the future risk of cognitive impairment in cognitively unimpaired older adults.

The study pooled data across six international cohorts (n = 2,684 participants) and found that higher baseline p-tau217 levels were associated with long-term clinical progression after adjustment for APOE ε4 status and amyloid PET imaging. While further validation in unselected, representative populations and the development of assay-specific thresholds are required before p-tau217-based estimates can guide individual prognosis, these findings may support the development of prognostic models and the design of preclinical Alzheimer disease trials.