Changes in arterial stiffness, cognition and dementia risk in a diverse cohort

中央动脉僵硬和血流搏动性增加改变了微血管的结构和功能 脑部导致低灌注率和终末器官损伤。反复出现微血管缺血 据报道，这会导致脑白质高信号、局灶性脑梗塞和脑萎缩。 认知障碍与轻度认知障碍(MCI)和阿尔茨海默病相关风险 痴呆症。而中央动脉僵硬与认知功能受损和脑功能异常有关 脑磁共振成像，到目前为止还没有研究动脉变化的影响的报告 僵硬和脉动对社区大脑结构、认知功能、MCI或痴呆症风险的变化- 此外，还没有评估性别和种族在这些协会中的重要作用。 我们建议在一项关于社区动脉粥样硬化风险的辅助研究中解决这些差距- 神经认知研究(ARIC-NCS)，一项正在进行的队列研究，对70-89岁的特征良好的个人进行研究 2011-2013年基线，5年后在非洲裔美国人和 白人男女。 2016-2018年对5,058名ARIC-NCS队列成员的重新检查将包括深入的心理测量学 评估，生物学和行为特征，以及MCI和痴呆的分类。这项辅助研究将 在2011-2013年测量的基础上增加动脉僵硬和搏动性的标准化重复测量。队列 因此，成员的特征将是中央动脉僵硬和脉动性的变化率 五年的进程及其时间变化的可改变的决定因素。关联将被量化 在这些中央动脉僵硬和脉动性的变化与脑白质高信号的变化之间， 发生局灶性脑梗塞、特定领域的认知功能，以及5年MCI和痴呆症的发病率。 假设MCI患者的关联性在基线、女性和 非裔美国人。 这项符合PAR-15-356的成本效益辅助研究将为 关于中央动脉僵硬和脉动性对脑结构和功能影响的有限知识基础 在老年人中发挥作用，并首次在非洲裔美国人的大样本中解决这些问题， 老年人动脉僵硬、MCI和痴呆症加重的人群。积累了关于 通过改变生活方式和目标血压来改变动脉僵硬和搏动性的能力 控制增加了这些问题的重要性，以努力减少MCI和 在老年痴呆症和促进我们老龄化人口的认知复原力。

Central arterial stiffness and increased blood flow pulsatility alter microvasculature structure and function in the brain contributing to hypoperfusion and end-organ damage. Repeated occurrences of microvascular ischemia reportedly lead to white matter hyperintensities, focal brain infarcts, and brain atrophy that contribute to cognitive impairment and the risk of mild cognitive impairment (MCI) and Alzheimer's disease-related dementias. While central artery stiffness is associated with impaired cognitive function and abnormalities on cerebral magnetic resonance imaging, no reports to date have examined the effect of changes in arterial stiffness and pulsatility on changes in brain structure, cognitive function, risk of MCI or dementia in community- dwelling older adults, nor have the important roles of gender and race in these associations been assessed. We propose to address these gaps in an ancillary study to the Atherosclerosis Risk in Communities – Neurocognitive Study (ARIC-NCS), an ongoing cohort study of well characterized individuals aged 70-89 years at baseline in 2011-2013, with repeat examinations to be conducted after 5 years in African American and white men and women. The 2016-2018 re-examination of 5,058 members of the ARIC-NCS cohort will include in-depth psychometric assessments, biologic and behavioral traits, and classification of MCI and dementia. This ancillary study will add repeat measures of arterial stiffness and pulsatility standardized to those measured in 2011-2013. Cohort members will thus be characterized on the rate of change in central arterial stiffness and pulsatility over the course of 5 years and the modifiable determinants of their temporal change. Associations will be quantified between these changes in central arterial stiffness and pulsatility with changes in white matter hyperintensities, incident focal cerebral infarcts, domain-specific cognitive function, and 5-year incidence of MCI and dementia. Associations are hypothesized to be stronger among those with MCI at baseline, among women, and among African Americans. This cost-efficient ancillary study in response to PAR-15-356 will contribute novel, prospective information to the limited knowledge base on the effects of central arterial stiffness and pulsatility on brain structure and function in older adults, and for the first time address these questions in a large sample of African Americans, a population burdened with greater arterial stiffness, MCI and dementia in older age. Accumulating evidence on the ability to modify arterial stiffness and pulsatility through changes in lifestyle and by targeted blood pressure control adds significance to these questions toward efforts to reduce the population burden of MCI and dementia, and in the promotion of cognitive resilience in our aging population.