ALZHEIMER’S DISEASE - ETIOPATHOGENESIS, CLINICAL PRESENTATION, AND CURRENT DIAGNOSTIC METHODS - A LITERATURE REVIEW
DOI:
https://doi.org/10.31435/ijitss.3(51).2026.5857Keywords:
Alzheimer's Disease, Neurodegeneration, Beta-Amyloid, Tau Protein, Neuroimaging, Cerebrospinal FluidAbstract
Introduction: Alzheimer’s disease (AD) is the most common cause of dementia, accounting for 60–80% of cases, and its prevalence is increasing as the population ages. It is estimated that approximately 50 million people worldwide currently live with dementia, and this number could triple by 2050. AD is a chronic, progressive, and incurable disease leading to significant disability and high healthcare costs. Neuropathologically, it is characterized by the presence of β-amyloid plaques and tau neurofibrillary tangles.
Aim of the study: The aim of this study was to present the current state of knowledge regarding Alzheimer’s disease, with particular emphasis on etiopathogenesis, risk factors, clinical symptoms, diagnostic methods, and modern biomarkers.
Material and methods: This is a review study based on an analysis of the current scientific literature on AD. The literature available in the PubMed and Google Scholar databases was analyzed using keywords.
Results and conclusions: A review of the literature indicates that AD is a disease with a complex pathogenesis involving β-amyloid accumulation, tau protein hyperphosphorylation, autophagy dysfunction, and genetic factors such as the APOE ε4 allele. Early symptoms mainly include memory and cognitive impairments. Biomarkers, including Aβ42/40, p-tau, NfL, and GFAP, as well as neuroimaging techniques such as MRI and PET, are of key importance in diagnosis. Early detection of the disease in the preclinical phase offers the possibility of implementing measures to slow its progression. Despite the lack of effective causal treatment, the development of biomarkers and diagnostic methods offers hope for improved early diagnosis and more effective monitoring of the disease’s progression.
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Copyright (c) 2026 Mateusz Cieciora, Małgorzata Kawiorska, Julia Surowiec, Aleksandra Cieciora, Katarzyna Zegadło, Katarzyna Kuc, Maciej Dobrucki, Krzysztof Brzezicki, Patryk Jakubiak, Wiktoria Bełcikowska-Skowron

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