Ringman John M, Medina Luis D, Rodriguez-Agudelo Yaneth, Chavez Mireya, Lu Po, Cummings Jeffrey L
Mary S. Easton Center for Alzheimer's Disease Research at UCLA, Associate Clinical Professor, UCLA Department of Neurology, 10911 Weyburn Ave., #200, Los Angeles, CA 90095-7226, USA.
Curr Alzheimer Res. 2009 Aug;6(4):341-6. doi: 10.2174/156720509788929336.
The definition of mild cognitive impairment (MCI) as a precursor for Alzheimer's disease (AD) represented an important step forward in diagnosing the illness in its earliest stage. However, diagnoses based principally on cognitive performance have limitations in that there is variability between centers in which tests are employed and in how they are interpreted. Advances in our understanding of imaging and biochemical changes occurring early in the illness have improved our ability to diagnose AD in this early phase and diagnostic criteria for AD have been proposed recently based on such biomarkers. Persons inheriting autosomal dominant mutations causing familial AD (FAD) are essentially certain to develop the disease. In our studies of preclinical persons at-risk for inheriting FAD, we applied MCI diagnostic criteria to carriers of FAD mutations to ascertain the extent to which they identified persons in the earliest stages of the clinical illness. Our results indicate the relative prevalence of MCI subtypes varies considerably depending on the tests used to measure cognition. Furthermore, we found that cognitive complaints in such persons were less predictive of mutation status than were informants' reports of cognitive loss. The study of FAD provides an opportunity to test various criteria for early AD and these observations should be taken into consideration in future iterations of such diagnostic criteria.
将轻度认知障碍（MCI）定义为阿尔茨海默病（AD）的前驱症状，这是在疾病最早期阶段进行诊断方面向前迈出的重要一步。然而，主要基于认知表现的诊断存在局限性，因为不同中心在使用测试方法以及对测试结果的解读方面存在差异。我们对疾病早期发生的影像学和生化变化的理解取得了进展，这提高了我们在疾病早期阶段诊断AD的能力，并且最近基于此类生物标志物提出了AD的诊断标准。遗传常染色体显性突变导致家族性AD（FAD）的人基本上肯定会患上这种疾病。在我们对有遗传FAD风险的临床前人群的研究中，我们将MCI诊断标准应用于FAD突变携带者，以确定这些标准在识别临床疾病最早阶段患者方面的程度。我们的结果表明，MCI亚型的相对患病率根据用于测量认知的测试方法而有很大差异。此外，我们发现，与信息提供者报告的认知能力丧失相比，这类人群的认知主诉对突变状态的预测性较低。对FAD的研究为测试早期AD的各种标准提供了机会，这些观察结果应在未来此类诊断标准的修订中予以考虑。
