Predicting Decline in Mild Cognitive Impairment

描述（由申请人提供）：轻度认知障碍（MCI）已被提出作为正常衰老和痴呆之间的中间地带，这一概念有望早期识别和治疗可能发展为阿尔茨海默病（AD）的个体。这一概念的预测价值的局限性是，每年只有一小部分MCI患者继续发展为AD（约12%）。如果从MCI转化为AD的个体更容易识别，那么临床试验可以更有效地进行。由于没有特定的生物医学/心理测量标记可用于识别这些潜在的转换器，本研究旨在利用一种新的范式来识别这些人谁是在更大的风险转换为AD。本项目的1个目标是确定实践效果的相对大小（即，由于重复暴露于测试材料而增加的认知测试性能）。最近，实践效果已被证明是有用的，在检测MCI，这些研究结果的逻辑延伸是评估他们的能力，以预测MCI下降。因此，第二个目标是确定练习效果在预测未来认知功能方面的相对价值。具体而言，我们提出了一个纵向观察研究，在老年受试者与NCI或MCI。所有参与者将接受认知功能的基线评估，并立即重复评估练习效果。预计NCI参与者将比MCI参与者表现出更大的实践效果。在MCI组中，一些人会表现出相对较大的练习效果，而一些人会表现出较小的练习效果。将在6个月和12个月时对所有参与者进行随访认知评估。据推测，在基线阶段表现出的练习量将与随访时的认知下降量呈负相关，这可能导致认知下降的早期识别。

DESCRIPTION (provided by applicant): Mild Cognitive Impairment (MCI) has been proposed as a middle ground between normal aging and dementia, and this concept holds promise for the early identification and treatment of individuals likely to develop Alzheimer's disease (AD). 1 limitation of the predictive value of this concept is that only a fraction of individuals with MCI go on to develop AD each year (approximately 12%). If the individuals who convert from MCI to AD were more easily identified, then clinical trials could be more efficiently conducted. Since no specific biomedical/psychometric marker is available that identifies these potential converters, the present study seeks to utilize a novel paradigm to identify these individuals who are at greater risk to convert to AD. 1 goal of this project is to determine the relative magnitude of practice effects (i.e., increased cognitive test performance due to repeated exposure to test materials) among elderly individuals with no cognitive impairments (NCI) or MCI. Recently, practice effects have been shown to be useful in detecting MCI, and a logical extension of these findings is to evaluate their ability to predict decline in MCI. Therefore, a second goal is to determine the relative value of practice effects in predicting future cognitive functioning. Specifically, we propose a longitudinal observational study in elderly subjects with NCI or MCI. All participants will receive a baseline assessment of cognitive functioning, which will be immediately repeated to assess practice effects. It is expected that participants with NCI will demonstrate larger practice effects than participants with MCI. It is also expected that within the MCI group, some individuals will display relatively larger practice effects and some will display smaller practice effects. Follow-up cognitive evaluations will be conducted on all participants at 6- and 12-months. It is hypothesized that the amount of practice demonstrated during the baseline phase will be inversely related to the amount of cognitive decline on follow-up, which could lead to earlier identification of cognitive decline.