Systematic Review of Challenges in Diagnostic Methods and Biomarkers for Alzheimer's Disease: Issues in Each Approach

Alzheimer's disease (AD) is a complex neurodegenerative disorder with increasing global prevalence, particularly due to aging populations. The economic burden of AD is significant, especially in cases of late diagnosis. Despite its critical importance, early diagnosis remains a major challenge, highlighting the need for effective and non-invasive diagnostic tools. This systematic review examines the challenges and opportunities in developing diagnostic kits for AD, focusing on their efficacy in detecting early-stage disease. The study reviews recent research (۲۰۲۰–۲۰۲۴) from reputable databases, considering only studies that provide quantitative and qualitative evaluations of these kits, including sensitivity, accuracy, and clinical utility. Key biomarkers, such as beta-amyloid (Aβ), amyloid precursor protein (APP), tau (τ) protein, and inflammatory factors, play crucial roles in AD diagnosis. Changes in beta-amyloid and tau levels in cerebrospinal fluid (CSF) and blood offer valuable insights into disease onset and progression. However, challenges remain regarding their sensitivity and accuracy in early-stage detection. This review explores diagnostic kits based on blood, urine, saliva, CSF, and sweat, discussing their limitations in terms of sensitivity, accuracy, and biological variability. Blood-based kits, in particular, are still in early development and show limited effectiveness in early diagnosis. Kits based on other biofluids face challenges such as low sensitivity, inter-individual variability, and environmental influences. Despite advancements in biomarker research and imaging technologies, non-invasive and cost-effective diagnostic kits still face significant limitations. Future studies should address these challenges and focus on improving precision and reliability for early AD detection and effective treatment.

کلیدواژه ها:

Alzheimer Disease ، Diagnostic kits ، Biomarkers ، Non-invasive diagnostics ، Invasive diagnostics