대한노인정신의학회

The development of blood-based biomarkers for Alzheimer’s disease (AD) has advanced significantly, driven by improvements in highly sensitive analytic platforms that support large-scale population screening. These biomarkers offer a promising alternative to conventional diagnostic tools such as positron emission tomography imaging or cerebrospinal fluid analysis, which are often constrained by cost, invasiveness, and limited accessibility. Widespread implementation of blood-based screening could improve diagnostic equity across diverse populations, particularly those with poor socioeconomic backgrounds, by facilitating the early identification of at-risk individuals who may then undergo confirmatory testing with traditional biomarkers. This approach has the potential to enhance diagnostic efficiency and reduce the burden on healthcare systems. Beyond early detection, blood biomarkers also offer valuable potential for monitoring therapeutic responses, especially in the context of disease-modifying therapies. This review highlights key biomarker candidates under active investigation, including amyloid-beta, phosphorylated tau isoforms, neurofilament light chain, and glial fibrillary acidic protein, as well as emerging markers such as neuron-derived exosome contents and transactive response DNA-binding protein 43. Despite encouraging progress, significant challenges remain. These include the need for analytical standardization, the establishment of clinically validated cutoff values, and the persistent underrepresentation of socioeconomically disadvantaged groups in research cohorts. Addressing these barriers will be essential for the broad clinical integration of blood-based diagnostics, ultimately contributing to earlier, more equitable detection and management of AD worldwide.

Alzheimer disease; Biomarkers; Blood; Dementia; Diagnosis.