Normative Values for Cognitive Testing and Alzheimer's Imaging Biomarkers in Young Adults

Study Overview
=================
Brief Summary
-----------------
Biomarkers of Alzheimer's disease (AD) occupy an essential place in recently formulated diagnostic criteria for AD where their role is to identify the pathophysiological processes underlying cognitive impairment or to predict time to dementia. Three of these biomarkers are brain imaging tests (amyloid PET, fludeoxyglucose (FDG) PET, and structural MRI). In order to effectively use AD biomarkers for diagnostic and prognostic purposes, continuous values much be divided into normal and abnormal ranges. This requires that a cut point(s) be established in the continuous distribution of values for each biomarker. The investigators objective in this proposal is to obtain imaging biomarker data in a group of individuals who are appropriate for establishing normative values for AD biomarkers. The investigators believe the most valid approach to establishing biomarker cut points is to base them on the upper bound of the range observed in young to early-middle-age subjects in whom the presence of occult AD pathology is extremely unlikely. Based on a large volume of community-based autopsy data, that upper age limit would be about 50 years old. The lower age bound for a group of subjects used to establish normative AD biomarker values would have to be based on considerations of brain maturation, which may continue into the middle- to late-20s. Thus, taking the above into consideration, the ideal age range for establishing normative AD imaging biomarker data (amyloid PET, FDG PET, and structural MRI) may be ages 30-49 years old.

Official Title
-----------------
Normative Values for Cognitive Testing and Alzheimer's Imaging Biomarkers in Young Adults (30-49yo)

Conditions
-----------------
Alzheimer's Disease

Intervention / Treatment
-----------------
* Drug: F-18 FDG
* Drug: C-11 PiB


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Cognitively normal males or females aged 30 to 49 years old. Exclusion Criteria: Subjects unable to lie down without moving for up to 45 minutes. Women who are pregnant or cannot stop breast feeding for 24 hours. Claustrophobic patients unable to tolerate the scans (no sedation can be offered). Standard safety exclusionary criteria for MRI such as metallic foreign bodies, pacemaker, etc.

Ages Eligible for Study
-----------------
Minimum Age: 30 Years
Maximum Age: 49 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Cognitively Normal Subjects<br>Study participation will consist of tests of memory and thinking, a MRI, and two PET scans. F-18 FDG and C-11 Pittsburgh compound B (PiB) are two drugs used in PET scans. | Drug: F-18 FDG<br>* One time intravenous administration of 17 millicurie (mCi) +/- 10%<br>Drug: C-11 PiB<br>* One time intravenous administration of 10-20 mCi<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Normal values for amyloid PET, FDG and Magnetic Resonance Imaging | Biomarkers of Alzheimer's disease (AD) occupy an essential place in recently formulated diagnostic criteria for AD where their role is to identify the pathophysiological processes underlying cognitive impairment or to predict time to dementia. Three of these biomarkers are brain imaging tests (amyloid PET, FDG PET, and structural MRI). In order to effectively use AD biomarkers for diagnostic and prognostic purposes, continuous values much be divided into normal and abnormal ranges. This requires that a cut point(s) be established in the continuous distribution of values for each biomarker. | 2 days |