Risk Factors for Cognitive Decline in African Americans

描述(由申请人提供)：与衰老相关的认知障碍是一个主要的公共卫生问题。鉴于非洲裔美国人在老年人口中的比例预计会增加，认知障碍的负担可能会在这一亚群中不成比例地增加。与衰老相关的认知障碍从根本上说是一个人的能力随着时间的推移而发生变化的过程，然而大多数关于非裔美国人认知障碍的研究都是横向的。由于很难解释与单一时间点的测试测量相关的文化和教育偏差，这些研究需要通过检查认知功能的变化来补充。拟议项目的目标是进行一项流行病学纵向研究，以确定老年非裔美国人认知功能变化的危险因素。由于认知是由可分离的系统组成的，这些系统调节特定类型的信息处理，因此我们不仅将评估认知的全球衡量标准，而且还将评估不同认知系统中的变化。假设1)拥有一个或多个载脂蛋白e4等位基因将预测整体认知功能的下降，特别是情景记忆；2)更多的教育年限和更高的一生参与认知活动的频率将预测更少的整体认知功能，特别是情景记忆、工作记忆和知觉速度的下降；以及3)更高水平的抑郁症状将预测更快的整体认知功能的下降，特别是情景记忆和视觉空间能力的下降。为了验证这些假设，我们将招募300名居住在社区的老年非裔美国人，他们在基线上没有痴呆症，并且有广泛的教育和终身环境经验，他们同意进行年度跟踪评估和详细的认知测试。少数族裔老龄化人口的快速增长增加了更好地了解与认知能力下降有关的风险因素的紧迫性。

DESCRIPTION (provided by applicant): Cognitive impairment associated with aging is a major public health problem. Given the expected increase in the proportion of African Americans among the older population, the burden of cognitive impairment is likely to increase disproportionately in this subgroup. Cognitive impairment associated with aging is fundamentally a process of change in an individual's ability over time, yet most studies of cognitive impairment in African Americans have been cross-sectional. Because of the difficulty in accounting for cultural and educational biases associated with test measurement at a single point in time, these studies need to be complemented by examination of change in cognitive function. The goal of the proposed project is to conduct an epidemiologic longitudinal study to identify risk factors for change in cognitive function in older African Americans. Because cognition is composed of dissociable systems that mediate specific types of information processing, we will assess change not only in a global measure of cognition, but in different cognitive systems as well. It is hypothesized that 1) the possession of one or more apolipoprotein e4 alleles will predict decline in global cognitive function, and specifically in episodic memory; 2) more years of education and higher frequency of participation in cognitive activity across the life span will predict less decline in global cognitive function and specifically in episodic memory, working memory, and perceptual speed; and 3) higher levels of depressive symptoms will predict more rapid decline in global cognitive function and specifically in episodic memory and visuospatial ability. To test these hypotheses we will enroll 300 older community dwelling African Americans without dementia at baseline, and with a wide range of educational and lifetime environmental experiences who agree to annual follow-up evaluations and detailed cognitive testing. The faster growth of the aging minority population adds urgency to the need for a better understanding of risk factors related to cognitive decline.