Early Vascular Contributions to Dementia Risk in African-Americans

非裔美国人的痴呆症和阿尔茨海默病的发病率比非西班牙裔美国人高40-100%。 白人和非洲裔美国人（AA）-美国老年人口增长最快的部分之一- - 如果这种趋势持续下去，将构成痴呆症“银海啸”的最大部分。理解 老年AA的认知老化代表了迫切的公共卫生需求。虽然认知能力下降和痴呆 是老年AA个体的主要健康问题，这是一个异质群体， 在生命过程中暴露和健康的差异影响晚年认知的变化是至关重要的， 制定干预措施并了解如何降低风险。认知功能的人群队列研究 AA中的老化很少，特别是那些在第五和第六个十年遵循认知老化轨迹的人。 生活AA有更高的中风，糖尿病和高血压的发病率，这些都是阿尔茨海默病的危险因素， 并且有更广泛的不良生活经历，这可能会影响晚年的认知健康。2013年 美国国立卫生研究院关于预防认知衰退的科学状态推荐了一种生命过程方法， 早期暴露与晚年大脑老化的关系。然而，虽然老年痴呆症的易感性增加， 血管疾病使AA成为确定生命过程暴露的关键群体，大多数已知的早期 老年痴呆症和认知老化的生命危险和保护因素主要来自于基于人群的 对非西班牙裔白人的研究我们提出了一个脑老化的生命过程研究，将利用50年的 前瞻性收集生活史和健康数据。我们的目标是：1）。 在一个具有代表性的基于人群的队列中， 美国人，2）。检查累积暴露于血管风险，心理社会因素和早期生活经验 超过50年，并评估对认知老化的影响，和3）。评价脑结构MRI成像标记物 特定领域认知功能的状态，并探讨大脑状态作为 生命过程因素和认知。研究结果将直接使阿尔茨海默病风险最高的人群受益 疾病和痴呆症在美国，已经从生命过程的角度研究不足， 预计到2030年，美国65岁以上人口的规模将增加一倍以上。

Rates of dementia and Alzheimer’s disease are 40-100% higher in African-Americans versus non-Hispanic whites, and African-Americans (AA) – one of the fastest-growing segments of the elderly population in the US - - will comprise the largest segment of the ‘silver tsunami’ of dementia if trends persist. Understanding cognitive aging in elderly AA represents an urgent public health need. Though cognitive decline and dementia are major health issues for older AA individuals, this is a heterogeneous group and understanding how differences in exposures and health over the lifecourse influence variability in latelife cognition is critical for developing interventions and understanding how to reduce risk. Population-based cohort studies of cognitive ageing in AA are few, specifically those which follow trajectories of cognitive aging in the 5th and 6th decade of life. AA have higher rates of stroke, diabetes and hypertension, established risk factors for Alzheimer’s disease, and have broader exposure to adverse life experience which may impact late-life cognitive health. The 2013 NIH State of the Science on Preventing Cognitive Decline recommended a lifecourse approach, incorporating early life exposures with brain aging in late life. Yet, while increased vulnerability to Alzheimer’s disease and vascular disease make AA a crucial group to identify lifecourse exposures, most of what is known about early life risk and protective factors of Alzheimer’s disease and cognitive aging is largely from populations based studies of non-Hispanic whites. We propose a lifecourse study of brain aging that will utilize 5 decades of prospectively collected life history and health data. Our goals are: 1).Characterize heterogeneity in longitudinal change in domain specific cognition in a representative population based cohort of well characterized African- Americans, 2). Examine cumulative exposure to vascular risk, psychosocial factors and early life experience over 50 years and evaluate effects on cognitive aging, and 3). Evaluate structural MRI imaging markers of brain status on domain-specific cognitive function and explore brain status as mediators of the association between lifecourse factors and cognition. Findings will directly benefit a population that is at highest risk of Alzheimer’s disease and dementia in the United States, has been understudied from a lifecourse perspective, and is expected to more than double in size by 2030 within the age 65+ segment of the US population.