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重大的公共卫生问题。鉴于非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个人能力随时间变化的过程，然而大多数关于非裔美国人认知障碍的研究都是横向的。由于很难在单一时间点上解释与测试测量相关的文化和教育偏差，这些研究需要通过对认知功能变化的检查来补充。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。因为认知是由可分离的系统组成的，这些系统介导特定类型的信息处理，所以我们不仅要评估认知的全球测量中的变化，还要评估不同认知系统中的变化。据推测，1)携带一个或多个载脂蛋白e4等位基因可以预测整体认知功能的下降，特别是在情景记忆方面；2)受教育年限越长，一生中参与认知活动的频率越高，整体认知功能的下降幅度越小，特别是在情景记忆、工作记忆和知觉速度方面；3)抑郁症状越严重，整体认知功能下降越快，尤其是情景记忆和视觉空间能力。为了验证这些假设，我们将招募300名居住在社区的非裔美国老年人，他们在基线时没有痴呆症，并且有广泛的教育和终身环境经历，他们同意每年进行随访评估和详细的认知测试。老龄化少数民族人口的快速增长增加了对更好地了解与认知能力下降相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.