Use of biomarkers in the early detection of Alzheimer’s disease

In 1906, Alois Alzheimer described the disease bearing his name, a progressive neurodegenerative pathology with high prevalence. This condition is characterized by progressive cognitive impairment, particularly memory loss, resulting from the degeneration and death of neurons in cortical and subcortical regions. Late diagnosis remains one of the main factors negatively impacting the prognosis of patients with Alzheimer’s disease (AD). Evidence from studies using positron emission tomography (PET) and cerebrospinal fluid (CSF) analysis indicates that neuropathological changes associated with AD begin up to 20 years before the onset of clinical symptoms. This study aims to present the growing role of biomarkers in the early detection of Alzheimer’s disease, emphasizing their importance in identifying early pathological changes before the appearance of clinical symptoms. This review seeks to investigate the use of biomarkers in the early detection of Alzheimer’s disease, focusing on articles from the last five years, both national and international. The methodology will be conducted systematically and structurally. The development of biomarkers for Alzheimer’s disease has advanced considerably, providing essential tools for the prevention, diagnosis, and monitoring of disease progression. Among the most studied biomarkers are Beta-Amyloid and phosphorylated Tau protein, which serve as biological indicators of the underlying pathological processes of the disease. These biomarkers can be measured objectively; however, obtaining this information often requires invasive methods, such as the collection of cerebrospinal fluid (CSF) to quantify protein levels. Phosphorylated Tau protein (p-tau), for instance, has proven particularly useful when combined with other biomarkers, offering a more accurate evaluation of the pathology. The integration of protein, genetic, and lipid biomarkers, together with new measurement platforms, will likely be essential in transforming the clinical approach to AD, providing a more comprehensive understanding of the disease from its early stages to its more advanced phases.