Study to Evaluate Amyloid in Blood and Imaging Related to Dementia

Study Overview
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Brief Summary
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The purpose of this study is to determine how well a blood test can detect amyloid beta, a protein involved in Alzheimer's disease. Participants will be asked to complete an initial blood collection and cognitive testing, and a subset of participants will be asked to complete a larger blood collection, amyloid PET imaging, and an MRI.

Detailed Description
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Alzheimer's disease is the most common cause of dementia and currently has no disease-modifying treatments or simple, accurate diagnostic tests. Amyloid beta builds up in the brain and forms plaques in people with Alzheimer's disease, and the buildup of this protein is found decades before symptoms of dementia begin. A blood test may be able to quickly and inexpensively screen people for Alzheimer's disease clinical trials and eventually diagnose Alzheimer's disease in the clinic.

Official Title
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Blood Amyloid-Beta Relationship With Amyloid Plaques and CSF Amyloid-Beta

Conditions
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Alzheimer Disease, Alzheimer Dementia

Intervention / Treatment
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* Other: Blood collection, PiB PET/MRI, and cognitive testing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. At least 60 years of age Exclusion Criteria: Unable to perform one or more activities of daily living (eating, bathing, dressing, ambulating, toileting) due to cognitive impairment or dependent on others due to cognitive impairment. Body weight of <100 pounds Active infectious disease (e.g., HIV, hepatitis B, hepatitis C) Bleeding disorder Taking an experimental drug for AD Blood donation in the last two months Blood transfusion in the last three months On hospice

Ages Eligible for Study
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Minimum Age: 60 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Cognitively normal<br>896 of the 1120 enrolled will not exhibit subjective impairment as defined by a brief clinical test. These participants will complete an initial blood collection and cognitive testing, and a subset of participants will be asked to return for a larger blood collection, amyloid (PiB) PET imaging, and MRI. | Other: Blood collection, PiB PET/MRI, and cognitive testing<br>* Blood and imaging results will be analyzed for amyloid beta. Cognitive testing will be performed to determine clinical and cognitive status.<br>|
| Cognitively impaired<br>224 of the 1120 enrolled will exhibit subjective impairment as defined by a brief clinical test. These participants will complete an initial blood collection and cognitive testing, and a subset of participants will be asked to return for a larger blood collection, amyloid (PiB) PET imaging, and MRI. | Other: Blood collection, PiB PET/MRI, and cognitive testing<br>* Blood and imaging results will be analyzed for amyloid beta. Cognitive testing will be performed to determine clinical and cognitive status.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma amyloid-beta 42/40 ratio |  | Baseline | 
| Plasma amyloid-beta 42/40 ratio |  | 6 months | 
| Area under the curve (AUC) of the blood test (plasma amyloid-beta 42/40 ratio) in predicting amyloid PET status |  | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Coefficient of variation for the initial and confirmatory blood amyloid-beta test results |  | 6 months |