Marcadores bioquímicos plasmáticos utilizados no diagnóstico da doença de Alzheimer: uma revisão integrativa.

Abstract

Alzheimer's disease is a common cognitive neuropathology in the elderly population, characterized by memory loss, confusion and difficulty in performing tasks. This disease has no cure and traditional diagnostic methods do not provide an early diagnosis, as they are highly invasive, expensive and require a long time for interpretation and issuance of the result. However, diagnosis by plasma biochemical markers has emerged as an option for early diagnosis, due to its low cost, agility and reliability when compared to classical diagnoses. Thus, the objective of this study was to conduct an integrative bibliographic review of the scientific literature on plasma biochemical markers used in the diagnosis of Alzheimer's disease. The search for material was carried out in the PubMed and Periódico CAPES databases, using the descriptors “Alzheimer disease”, “Laboratory test”, “plasma biomarker”, “clinical diagnostic”, “Tau proteins” and “Amyloid beta” and refining the articles between the months of January 2020 to July 2024. A total of 135 articles were found, 24 of which were included in this study. Based on the main results found, the plasma biochemical markers that can aid in the diagnosis of Alzheimer's disease, both in combination and isolated, are phosphorylated tau protein 181 (p-tau181), phosphorylated tau protein β17 (p-tauβ17), phosphorylated tau protein βγ1 (p-tauβγ1), glial fibrillary acidic protein (GFAP) and beta-amyloid peptide (Aȕ) due to their good sensitivity and specificity rates. On the other hand, it was found that total tau and neurofilament light chain did not present good sensitivity and specificity results, respectively, so it is recommended to use them only together. It is worth noting that these markers showed a good predictive capacity in relation to Alzheimer's disease, but the development of a more robust and qualified analytical methodology is necessary to quantify these markers in an unequivocal, agile and reproducible manner.