Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing 100053, China.
Department of Neurology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230022, China.
Chin Med J (Engl). 2023 Mar 5;136(5):505-521. doi: 10.1097/CM9.0000000000002566.
Alzheimer's disease (AD) is a neurodegenerative disease that gradually impairs cognitive functions. Recently, there has been a conceptual shift toward AD to view the disease as a continuum. Since AD is currently incurable, effective intervention to delay or prevent pathological cognitive decline may best target the early stages of symptomatic disease, such as subjective cognitive decline (SCD), in which cognitive function remains relatively intact. Diagnostic methods for identifying AD, such as cerebrospinal fluid biomarkers and positron emission tomography, are invasive and expensive. Therefore, it is imperative to develop blood biomarkers that are sensitive, less invasive, easier to access, and more cost effective for AD diagnosis. This review aimed to summarize the current data on whether individuals with SCD differ reliably and effectively in subjective and objective performances compared to cognitively normal elderly individuals, and to find one or more convenient and accessible blood biomarkers so that researchers can identify SCD patients with preclinical AD in the population as soon as possible. Owing to the heterogeneity and complicated pathogenesis of AD, it is difficult to make reliable diagnoses using only a single blood marker. This review provides an overview of the progress achieved to date with the use of SCD blood biomarkers in patients with preclinical AD, highlighting the key areas of application and current challenges.
阿尔茨海默病（AD）是一种神经退行性疾病，会逐渐损害认知功能。最近，人们对 AD 的认识发生了转变，将其视为一种连续体。由于 AD 目前无法治愈，因此有效干预以延缓或预防病理性认知下降的最佳目标可能是针对有症状疾病的早期阶段，如主观认知下降（SCD），在此阶段认知功能仍相对完整。用于识别 AD 的诊断方法，如脑脊液生物标志物和正电子发射断层扫描，具有侵入性且昂贵。因此，迫切需要开发出对 AD 具有敏感性、侵入性较小、更易获得且更具成本效益的血液生物标志物。本综述旨在总结目前关于 SCD 个体与认知正常的老年人相比，在主观和客观表现上是否可靠且有效地存在差异的相关数据，并找到一种或多种方便且可获得的血液生物标志物，以便研究人员能够尽快在人群中识别出具有临床前 AD 的 SCD 患者。由于 AD 的异质性和复杂发病机制，仅使用单个血液标志物进行可靠诊断具有一定难度。本综述概述了迄今为止在使用 SCD 血液生物标志物诊断临床前 AD 方面取得的进展，重点介绍了其主要应用领域和当前挑战。
