ALZHEIMER'S DISEASE AND PROGRESSIVE COGNITIVE DECLINE

Abstract

This article presents an integrative literature review aimed at investigating the role of biomarkers in the diagnosis and monitoring of Alzheimer’s disease (AD), considering the need for methods capable of identifying the pathology at an early stage. The study was motivated by the persistent challenges involved in early diagnosis and by the search for tools that enhance clinical accuracy. AD is a progressive and irreversible neurodegenerative disorder characterized by the loss of cognitive functions and is responsible for most dementia cases in individuals over 65 years of age. The objective of this article is to analyze the main biomarkers used in the assessment of AD, with emphasis on β-amyloid, tau proteins, and neuroimaging techniques. The research was conducted through a bibliographic survey in the PubMed Central, SciELO, and Google Scholar databases, including studies published in the last five years. The analyzed studies revealed advances in the clinical application of biomarkers, showing that decreased β-amyloid and increased total and phosphorylated tau in the cerebrospinal fluid are directly associated with neuropathological changes characteristic of the disease. Modern neuroimaging techniques also demonstrated high sensitivity in detecting structural and functional alterations in early stages. Biomarkers have revolutionized AD diagnosis by enabling early identification and differentiation from other dementias. Although no cure currently exists, early diagnosis and clinical monitoring allow for more effective treatments and improved quality of life for patients.