Emerging Biomarkers for Early Detection of Alzheimer’s Disease: A Systematic Review

Alzheimer’s disease is primarily characterized by the gradual progression of neurodegeneration that leads to cognitive decline, and its early diagnosis remains the cornerstone for effective interventions. This systematic review of the current literature will investigate and summarize the available knowledge regarding the emerging biomarkers for the early diagnosis of AD. Many databases were searched across a wide range, using articles from the last ten years, all dealing with biochemical, imaging, and genetic biomarkers in the preclinical and prodromal stages of Alzheimer’s disease. More key biomarkers are those in cerebrospinal fluid, which are CSF markers like amyloid-beta (Aβ42) and tau proteins. Novel biomarkers are within the blood, through neuroimaging studies that use techniques such as PET and MRI. Genetic markers include the one APOE ε4. Findings hold promise for using biomarker profiles, especially fluid biomarkers combined with advanced neuroimaging, to enhance diagnostic accuracy at early stages. Such biomarkers require validation, however, through large-scale and longitudinal studies before their routine use in clinical settings. Standardized assessment protocols on the biomarker domain take on importance in this light to highlight the potential of new biomarkers in changing the landscape of diagnosis for AD.