We will capture subjects under another study

To advance current knowledge on the vascular contributions to dementia

This is a multi-center study at Washington University (WASH U), University of Southern California (USC), and Huntington Medical Research Institute (HMRI).The overall goal of both the AA program and the PPG program is to advance current knowledge on the vascular contributions to dementia particularly in individuals with the major genetic risk factor for late-onset AD, i.e., apolipoprotein E-ε4 (APOE4) gene that develop early vascular dysfunction and significant cerebrovascular pathology compared to non-carriers, and establish whether the neurovasculature plays a key role in cognitive decline, and therefore is a key new therapeutic target to treat dementia in APOE4 carriers.

Inclusion Criteria:

• Male or female, any race
• Age > 18 years
• Participation in one of the ongoing projects affiliated with the Knight ADRC at Washington University and referred by the MAP staff and a Washington University physician.
• Normal cognition or early-stage symptomatic AD
• Females of childbearing potential without documented history of menopause or hysterectomy who do participate must not be pregnant or breastfeeding at screening
• (negative urine β-HCG within 24 hours prior to injection), and must agree to avoid becoming pregnant. Females of childbearing potential who do not agree to use reliable contraception or refrain from sexual activity for 24 hours following administration of flortaucipir injection.
• Enrollment in DCE-MRI study
• Capacity to give informed consent and follow study procedures

Exclusion Criteria:

• Any illness preventing cooperation with testing or longitudinal participation
• Exclusion from the Knight ADRC or DIAN referring project
• Has a high risk for Torsades de Pointes or is taking medications known to prolong or may prolong QT interval (refer to study attachment "Restricted Medication List").
• MRI contraindications (e.g. electronic medical devices, severe claustrophobia, inability to lie still for long periods) that make it unsafe to participate in an MRI scan, using standard screening processes implemented by Washington University and Barnes-Jewish Hospital
• Currently pregnant or breastfeeding

A total of participants currently enrolled in ongoing projects affiliated with the Knight ADRC will be recruited. Without disclosing individual genetic risk status, 202 of these participants will include a mix of APOE4/4 (~7%), APOE3/4 (~30%), and APOE3/3 (~63%) carriers. In addition, without disclosing individual mutation status, ~40 PSEN1 carriers and non-carrier family members currently enrolled in the Dominantly Inherited Alzheimer Network (DIAN) study at Washington University will be recruited.

We will share the data with other researchers. They may be doing research in areas similar to this research or in other unrelated areas. These researchers may be at Washington University, at other research centers and institutions, or industry sponsors of research. We may also share the research data with large data repositories (a repository is a database of information) for broad sharing with the research community. The participant"s individual research data is placed in one of these repositories only qualified researchers, who have received prior approval from individuals that monitor the use of the data, will be able to look at this information.