Cardiovascular and Cerebrovascular Risk Factors for Mobility Limitation in the Jackson Heart Study

摘要 步行是人类生活的核心活动。活动受限，或行走困难或无法行走，会限制一个人的活动能力。 工作能力，独立生活，并参与社区。心脏和大脑的健康是两个 最强的可改变的途径来限制移动性。非裔美国人有不成比例的负担， 心血管疾病（CVD）、脑血管疾病（CBVD）、认知障碍和活动受限， 但大多数关于这些条件之间关系的研究主要是在 白色人口。生物学和最佳预防策略的行动限制可能会有所不同， 种族/民族，强调了在代表性不足的人口中进行研究的迫切需要。拟议研究 将在杰克逊心脏研究（JHS）中增加经验证的活动性、残疾和身体表现指标， 一项针对非裔美国人的队列研究，旨在调查高危人群中CVD的原因。JHS 参加者已接受三次考试（考试1，2000-2004，考试2，2005-2008，考试3，2009-2013）; 第四次考试计划从2020年开始对剩余的3,500名参与者（平均年龄= 65岁）进行。考试 将包括广泛的心血管疾病的措施，社会经济地位，心理健康，认知测试，和大脑 核磁共振我们提出了一项辅助研究，以增加既定的行动限制措施：步态速度<0.6 m/s， 并且自我报告难以/无法行走四分之一英里或爬10级楼梯。我们将利用近20个 年CVD/CBVD风险因素数据和新收集的亚临床血管疾病和脑血管疾病数据 健康，以更好地了解暴露于风险因素的时间和调解途径的流动性限制 在非裔美国人中。我们假设暴露于高血压，高空腹血糖， 中年肥胖症与老年人的活动受限之间的联系比暴露于这些疾病之间的联系更强。 晚年的危险因素我们将使用新的统计中介方法来量化潜在的 介质解释了CVD/CBVD风险因素与活动受限之间的关系，同时允许我们 测试这些介质的潜在相互作用。这项研究将支持我们的长期目标， 非裔美国人的功能性健康，以保持独立和参与 社区了解心脏和大脑健康与活动受限之间的联系对于减少 健康方面的种族差异。此外，增加功能措施将有助于将JHS扩展为 当代研究心血管健康和非洲裔美国人的老龄化。

ABSTRACT Walking is a core activity of human life. Mobility limitation, or difficulty or inability to walk, can limit a person's ability to work, live independently, and participate in the community. Heart and brain health are two of the strongest modifiable pathways to mobility limitation. African Americans have a disproportionate burden of cardiovascular disease (CVD), cerebrovascular disease (CBVD), cognitive impairment, and mobility limitation, but the majority of research on the relationship between these conditions has been conducted in predominantly white populations. The biology and optimal prevention strategies for mobility limitation may differ by race/ethnicity, highlighting a critical need for research in underrepresented populations. The proposed research will add validated measures of mobility, disability, and physical performance to the Jackson Heart Study (JHS), a cohort study of African Americans, designed to investigate causes of CVD in a high-risk population. JHS participants have undergone three exams (Exam 1, 2000-2004, Exam 2, 2005-2008, Exam 3, 2009-2013); Exam 4 is scheduled on the 3,500 remaining participants (mean age = 65 years) beginning in 2020. The exam will include extensive CVD measures, socioeconomic status, psychosocial health, cognitive testing, and brain MRI. We propose an ancillary study to add established measures of mobility limitation: gait speed <0.6 m/s, and self-reported difficulty/inability to walk a quarter of a mile or climb 10 stairs. We will leverage the nearly 20 years of data on CVD/CBVD risk factors and newly collected data on subclinical vascular disease and brain health to better understand the timing of exposure to risk factors and mediating pathways to mobility limitation in African Americans. We hypothesize that exposure to high blood pressure, high fasting glucose, and adiposity in midlife will have stronger associations with mobility limitation in older adults than exposure to these risk factors in late life. We will use novel statistical mediation methods to quantify the extent to which potential mediators explain the relationship between CVD/CBVD risk factors and mobility limitation, while allowing us to test for potential interactions by these mediators. This research will support our long-term goal to enhance functional health among African Americans, in order to preserve independence and participation in the community. Understanding the link between heart and brain health and mobility limitation is critical to reduce racial disparities in health. Moreover, the addition of the functional measures will help expand JHS into a contemporary study cardiovascular health and aging in African Americans.