[New blood-based biomarkers for Alzheimer's disease].

Blood-based biomarkers, particularly plasma p-tau217, have rapidly improved the detection of Alzheimer's disease pathology and can in some settings replace cerebrospinal fluid analysis or amyloid PET in clinical diagnostics. Clinically available assays now achieve high accuracy, especially when using a two-cutoff approach that classifies results as negative, intermediate, or positive, thereby supporting their use for confirming or ruling out disease. Implementation is likely to be straightforward in specialized clinics but more challenging in settings without prior biomarker experience or access to confirmatory testing for intermediate results, such as primary care.