Abstract / Summary
Alzheimer’s disease (AD) represents a growing global public health burden driven by progressive population aging. Early identification of AD-related pathological alterations is essential for timely intervention and risk stratification; however, currently available screening approaches remain constrained by subjectivity, limited accessibility, high cost, or procedural invasiveness. Plasma phosphorylated tau217 (p-tau217) has emerged as a highly sensitive and specific peripheral biomarker of AD-related tau pathology. Concurrently, eye-tracking technology offers an objective, noninvasive, and quantitative approach for evaluating cognitive and neurobehavioral function. Nevertheless, the relationship between eye movement behavioral parameters and plasma p-tau217 levels remains insufficiently characterized. This cross-sectional study enrolled 153 participants aged ≥ 50 years from a single neurology center. Eye-tracking parameters, including mean novel image dwell time, novelty preference ratio, and correct saccade latency, were assessed using a portable tablet-based eye-tracking platform. Plasma p-tau217 concentrations were quantified using a high-sensitivity chemiluminescence immunoassay. Associations between eye movement indices and plasma p-tau217 levels were analyzed using Spearman rank correlation. Multiple linear regression analyses were subsequently performed to identify independent factors associated with plasma p-tau217 after adjustment for potential confounding variables. Plasma p-tau217 levels demonstrated significant negative correlations with mean novel image dwell time ( r = − 0.290, P < 0.001), novelty preference ratio ( r = − 0.214, P = 0.008), and correct saccade latency ( r = − 0.166, P = 0.043). Following adjustment for confounding factors and assessment of multicollinearity, mean novel image dwell time remained independently associated with plasma p-tau217 concentrations (standardized β = −0.266, P = 0.001). Reduced novel image dwell time was associated with elevated plasma p-tau217 levels. Mean novel image dwell time, an indicator of visual novelty preference, showed a weak-to-moderate independent inverse association with plasma p-tau217 levels. These preliminary findings indicate eye-tracking behavioral metrics correlate with AD-related peripheral tau levels. This tablet-based eye movement paradigm shows potential auxiliary reference value for community cognitive risk evaluation, while further external cohort validation is essential before it can serve as an auxiliary reference marker in clinical cognitive evaluation.