The ARIC-PET Amyloid Imaging Study

描述(申请人提供)：随着美国人口老龄化，开发痴呆症预防和治疗的重要性日益明显。有证据表明，某些血管风险因素，如高血压、吸烟和糖尿病，特别是在中年发生时，可能会导致晚年患痴呆症的风险，甚至可能导致阿尔茨海默氏症(AD)，这是导致痴呆症的最常见原因。因此，解决与血管疾病相关的致病因素可能是预防痴呆症的一个重要因素。目前尚不清楚的是，血管风险因素是否真的会导致导致AD的大脑变化(具体地说，是β-淀粉样斑块)，还是阿尔茨海默氏症和大脑中的血管变化共同导致痴呆症恶化。本研究将探讨这两个假说。ARIC-PET淀粉样成像研究是社区动脉粥样硬化风险研究(ARIC)的辅助研究，这是一项大型研究，25年前开始时，涉及代表美国4个不同社区的16,000名个人。2011-2013年，作为目前资助的ARIC神经认知(ARIC-NCS)研究的一部分，幸存者将接受神经学评估、认知评估，并在子集中接受脑磁共振检查。我们将招募来自马里兰州杰克逊市、MS或黑格斯敦的210名年龄在70-90岁之间、认知正常或轻度认知障碍的人进行正电子发射计算机断层扫描，18F-AV-45是用于识别大脑中β-淀粉样蛋白的标记。在研究的最后两年，参与者将接受后续的认知评估。这项研究将确定：1)血管风险因素和标志物，特别是来自中年的血管风险因素和标志物，是否与β-淀粉样蛋白结合增加有关，这将表明血管疾病直接导致大脑中的AD变化；或2)大脑中的β-淀粉样蛋白沉积是否与血管风险因素和标志物一起导致认知障碍和痴呆症的发展。研究结果可能有助于优化未来对有痴呆风险的轻度认知障碍患者的治疗和预防试验。如果发现血管疾病与β-淀粉样斑块沉积之间有很强的相关性，这将为积极的危险因素治疗提供支持，以此作为减少认知能力下降和痴呆症发病率的一种手段。

DESCRIPTION (provided by applicant): With the aging of the U.S. population, the importance of developing preventions and treatments for dementia is increasingly apparent. Evidence suggests that certain vascular risk factors like hypertension, smoking and diabetes, especially when they occur in midlife, may contribute to risk for dementia in late life, and possibly even to Alzheimer's dementia (AD), the most common cause of dementia. Thus, addressing the contributing factors related to vascular disease may be an important element in dementia prevention. What is not well understood is whether vascular risk factors actually cause the changes in the brain that cause AD (specifically, β-amyloid plaques) or if having both Alzheimer's and vascular changes in the brain together makes the dementia worse. This study will explore these two hypotheses. The ARIC-PET Amyloid Imaging Study is an ancillary study of the Atherosclerosis Risk in Communities (ARIC) study, a large study involving, at its start 25 years ago, 16,000 individuals representative of 4 diverse U.S. communities. In 2011-2013, as part of the currently funded ARIC Neurocognitive (ARIC-NCS) study, the survivors will undergo neurologic evaluation, cognitive assessment, and, in a subset, brain MRI. We will recruit a further subset, 210 individuals aged 70-90 years from Jackson, MS or Hagerstown, MD with either normal cognition or mild cognitive impairment (MCI), to undergo a PET scan with 18F-AV-45, which is a marker used to identify β-amyloid in the brain. In the last 2 years of the study, participants will undergo follow-up cognitive evaluation. The study will determine: 1) whether vascular risk factors and markers, especially from midlife, are associated with increased β-amyloid binding, which would indicate that vascular disease directly contributes to AD changes in the brain, or 2) whether β-amyloid deposits in the brain in combination with vascular risk factors and markers contribute to cognitive impairments and development of dementia. Study results may help optimize future treatment and prevention trials in individuals with mild cognitive impairment who are at risk for dementia. If strong associations are found between vascular disease and β-amyloid plaque deposition, this will provide support for aggressive risk factor treatment as a means to decrease cognitive decline and incidence of dementia.