AIMS: 

• The Alzheimer’s Disease Research Center (ADRC) program includes over 35 centers across the USA.
• The SCAN project (Standardized Centralized Alzheimer’s and related dementias Neuroimaging) began in 2020.
• SCAN standardizes methods for acquisition, quality control, and analysis of MRI and PET across the ADRC network.
• ADRC sites each scan their own selected cohorts and submit protocol-compliant images to SCAN for QC, analysis, and public distribution.
• SCAN-collected images and analyses are shared via the National Alzheimer’s Coordinating Center (NACC) and the Laboratory of Neuroimaging at USC (LONI).
• Images are linked with richly characterized, harmonized clinical, psychometric, fluid biomarker, genetic, and neuropathology data (UDS) also available at NACC from across the ADRC network.

METHODS:

• SCAN includes an unusually high proportion of participants with atypical AD phenotypes (e.g. PCA, PPA, dysexecutive) and non-AD etiologies including FTLD, DLB, CBD, and vascular brain injury, and those with multiple etiologies.
• SCAN imaging methods are also identical to those in other large research datasets, facilitating analyses across major public datasets, including: ADNI, CLARiTI, HEAD, US POINTER, MCSA

RESULTS:

• SCAN includes de-identified and de-faced imaging data from 7,848 participants.
• Roughly 60% of SCAN participants are cognitively unimpaired, 20% have MCI, and 16% have dementia.
• Among the cognitively impaired individuals:
  • 29% had a predominantly non-amnestic initial presentation.
  • 16% have suspected primarily vascular etiology.
• 74% of participants have longitudinal data from more than one visit.
• The median age is 72 years old, and 59% are female.
• Nearly 30% identify as ethnoracial groups typically underrepresented in the USA.
• 1,532 (19.5%) have full A-T-N data available (MRI + Amyloid PET + Tau PET).

CONCLUSIONS:

• SCAN imaging data are available to all qualified researchers.
• SCAN provides images and standardized ATN imaging biomarkers for a richly characterized, highly heterogeneous group of cognitively unimpaired individuals and those with AD, non-AD, and multiple dementia etiologies.
• SCAN data well complements other public aging and dementia research datasets to enrich analyses with non-AD dementias, atypical phenotypes, and under-represented demographic groups.