Translating blood-based biomarkers into Alzheimer’s disease clinical practice: screening, diagnosis, and longitudinal monitoring
Blood-based biomarkers (BBMs) are increasingly being integrated into Alzheimer’s disease (AD) clinical pathways by providing scalable tools to track amyloid, tau, neurodegeneration, and inflammation dimensions of the ATN-I framework. As biological characterization and biomarker-informed assessment are increasingly integrated into AD care, there is growing interest in clinically applicable blood-based approaches capable of reflecting AD-related biological changes across different disease stages. This review examines recent advances in BBMs through the ATN-I framework while emphasizing their clinical decision value, analytical feasibility, economic considerations, and implementation barriers across different healthcare settings. Building on these findings, we examine the evidence supporting clinical use, with a focus on appropriate use criteria, clinical validation, laboratory feasibility, and consistent interpretation methods. Furthermore, this review explores how integrating BBMs with traditional cerebrospinal fluid and neuroimaging tests may support symptom-driven clinical triage, probability refinement, and early evaluation in selected individuals, improving clinical workflow efficiency and accessibility. Finally, the article addresses remaining challenges related to clinical validation, platform accessibility, cost-effectiveness, and equitable deployment, highlighting how emerging biomarker strategies may contribute to more scalable AD assessment.