Unlocking the Predictive Power of Plasma Biomarkers for Early Alzheimer’s Disease Detection

Introduction

Alzheimer’s disease (AD) remains a leading cause of dementia worldwide, with an urgent need for early detection strategies that can guide intervention before irreversible cognitive decline occurs. Traditionally, AD diagnosis has relied on clinical assessments complemented by neuroimaging and cerebrospinal fluid (CSF) biomarkers; however, these methods are often invasive, costly, or not widely accessible. Recent advances in blood-based biomarkers offer a promising avenue for scalable, minimally invasive screening, particularly in cognitively unimpaired populations at risk.

This review critically examines the findings from the study titled “Association of plasma Alzheimer’s disease biomarkers with cognitive decline in cognitively unimpaired individuals” by Cogswell et al., published in 2025. The study evaluates plasma phosphorylated tau217 (%p-tau217) and amyloid PET imaging in predicting transition from normal cognition to mild cognitive impairment (MCI), drawing data from the Mayo Clinic Study of Aging (MCSA) and BioFINDER-2 cohorts.