Over the past several years considerable research on biomarkers for Alzheimer’s disease as well as other dementias has rapidly progressed. Biomarkers in both CSF and blood have been studied as measurements of abnormal changes in the brain which could aid in the early detection of possible AD in people with mild or unusual symptoms. Since individuals with AD tend to progress at different rates during the course of the disease, biomarkers may help to predict and monitor progression. Moreover, biomarkers may hold promise to assist in the diagnosis and treatment of AD as well as in effective drug development for treating AD.
Currently, biomarkers are used to assist research studies on the early detection, prevention, and effects of potential treatments. Measurement of certain biomarkers may help researchers to understand how risk factors and genetic variants are involved in AD and select patients for clinical trials and research studies. In addition, biomarkers can be used to track study participants responses to a test drug or other intervention.
As previously discussed, Imaging studies using PET markers of amyloid-β and tau proteins have been employed with considerable accuracy to detect the presence of AD-associated pathophysiological and neuropathological changes. However, PET imaging carries a high cost and is often not sufficiently accessible for many patients. This limits the use of PET imaging as a viable first-line procedure for the detection of pathophysiologic patterns in AD.
Research has demonstrated that abnormal levels in CSF of certain biomarkers such as tau protein (phosphorylated tau) and the amyloid beta peptide such as AB-42 have been identified in patients with AD. Clinical studies have been performed and continue to be performed to determine the diagnostic utility of these and other biomarkers.