Contemporary diagnosis of Alzheimer's disease: IImportance of different biomarkers

Abstract

In preparation for the approval of new therapies for Alzheimer's disease (AD), a key step is the selection, validation and application of screening tests for disease detection and treatment monitoring. Biomarkers for AD have significantly advanced the field in several ways and hold promise for early diagnosis, determination of pathology, and measurement of response to treatment. The classic pathophysiological features of AD (beta-amyloid Ab (A), tau (T) and neurodegeneration (N) can be determined in the cerebrospinal fluid (CSF), but their presence can also be demonstrated by different imaging techniques such as Positron Emission Tomography (PET), either with an amyloid marker or with tau-ligand as the gold standards of amyloid and tau pathology, in trials in clinical practice. Currently, there are no widely accepted blood tests for neuroinflammation, astrocytic, microglial activation in AB. However, both methods are either invasive and/or very expensive at the same time, so great efforts have been made to determine basic and more specific biomarkers in blood as a less invasive and more accessible procedure. In the primary health care setting, diagnostic algorithms from blood could already be sufficient to improve the accuracy of the clinical diagnosis of AB dementia and to positively influence the future treatment and care of people with cognitive problems. Additional studies are needed to evaluate the optimal combination of plasma biomarkers with other accessible and cost-effective procedures, such as, for example, MRI and cognitive tests, which are necessary for further development of predictive algorithms, which will be especially important in non-demented patients with cognitive problems.