Abstract Body

Two blood-based biomarkers have been analytically and clinically validated as biomarkers for Alzheimer’s disease (AD) pathophysiology: the ratio of the 42 to 40 amino acid-long amyloid β as a marker of amyloid plaque pathology, and phosphorylated tau as a marker of AD-related tau phosphorylation and secretion. Additionally, serum neurofilament light (NfL) can be used as a general (non-specific) marker of neurodegeneration. Here, I give an updated account of the current state of the blood-based AD biomarker research field. I discuss how the new blood tests may be used in research studies, as well as in clinical trials and practice, and what role they may play in relation to more established diagnostic tests, such as cerebrospinal fluid biomarkers and amyloid and tau positron emission tomography, in the clinical work-up of patients with suspected AD.