Accelerated Non-Atherosclerotic Brain Arterial Aging Relationship to Alzheimer's Disease

The aging of the United States (US) population will lead to a steep rise in Alzheimer disease (AD). There is an urgent need for novel therapies that may tackle this looming societal problem. People with Alzheimer disease have frequently evidence of vascular disease in the brain, and vascular disease can increase the risk of Alzheimer disease. Based on this finding, the investigators plan to expand the understanding of how vascular disease contributes to Alzheimer disease, hoping to identify novel target to modify the natural progression of the disease. The investigators will accomplish this goal by inviting 300 participants (with and without dementia) of the Northern Manhattan Study (NOMAS) to undergo a brain magnetic resonance imaging (MRI) and donate blood. Of the 300 participants enrolled, 60 participants will be randomly selected to undergo Aβ and tau positron emission tomography (PET) imaging. From the brain MRI, the investigators will obtain measurements of cerebrovascular disease and relate the to the risk of Alzheimer disease. With the blood, the investigators hope to identify measures of aging and inflammation that may predict changes noted in brain scan and identify people at a higher risk of dementia. The investigators will examine PET markers of inflammation and aging in the brain and how the markers relate to dementia.