Fluid Biomarkers in Alzheimer’s Disease and Frontotemporal Dementia

Abstract

Fluid biomarkers, including cerebrospinal fluid (CSF) biomarkers and blood-based biomarkers, may reflect different pathological processes in Alzheimer’s disease (AD) and frontotemporal dementia (FTD). The most used biomarkers are CSF β-amyloid42, total tau, phosphorylated tau, and neurofilament light, which have been studied for diagnosis, prognosis, and treatment follow-up and in relation to genetics and neuroimaging. These biomarkers are now increasingly used in research, drug development, and clinical settings to increase our understanding of AD and FTD and to improve patient management. Recent progress in stable, automated assays for CSF biomarkers and ultrasensitive assays for blood-based biomarkers and the incorporation of fluid biomarkers in clinical practice and in clinical trials have accelerated the field. Key issues for further research include more extensive studies of the earliest stages of neurodegenerative diseases, better biomarkers for distinct proteinopathies, and the creation of universally accepted guidelines specifying the role of fluid biomarkers in relation to clinical measures and neuroimaging findings.