Clinic‐based data serving Population Neuroscience: NACC example

Abstract

AbstractBackgroundMemory clinics have historically driven case‐definition, clinical diagnostic criteria, and treatment trials in Alzheimer’s disease and related disorders (ADRD) and investigated neuroimaging and molecular factors leading to the development of ADRD biomarkers. The Uniform Data Set (UDS) of the National Alzheimer’s Coordinating Center (NACC)1 provides one such repository of clinic‐based and neuropathologic data2. (https://naccdata.org) With standardized characterization, long followup with low attrition, and post‐mortem neuropathology, memory clinic studies have high internal validity. However, they are rightly faulted for low external validity (generalizability) of results, with samples not representative of definable segments of the general population3. NACC has advanced several research directions proposed by the emerging field of Population Neuroscience.4 MethodApproximately 35 U.S. Alzheimer’s Disease Research Centers (ADRCs) enroll ADRD participants. Standardized (e.g., UDS) data collection and clinico‐pathologic correlations contribute to expanding phenotypic detail and support molecular biomarker, genomics, and soon, metabolomic analyses. NACC data support behavioral intervention trials and are now being used to characterize inadequately studied groups. NACC collaborates with ADRC consortia to facilitate studies of genomics, metabolomics, biomarkers, behavioral and environmental factors. Consortia datasets are interoperable with NACC1 offering opportunities to link UDS with GWAS and genome sequencing data (through NIAGADS), and soon with prospectively collected, standardized imaging biomarker data (through the SCAN project) with other collaborators.ResultBy December 2020, NACC had data from 43,517 participants including 15,440 with normal cognition, 9453 MCI, and 18,627 dementia; 30,019 have at least two longitudinal visits. 6,416 deceased participants have provided standardized neuropathology data. This NACC “case series” has generated >500 publications; NACC data are freely available to researchers worldwide.ConclusionClinic‐based studies function as laboratories observing potential data patterns and associations as a first step towards validation in more representative populations. NACC continues to make its data more “findable, interoperable, accessible and reusable” for the broader scientific community. Reference: 4. Ganguli M, Albanese E, Seshadri S, et al. Population Neuroscience: Dementia Epidemiology Serving Precision Medicine and Population Health. Alzheimer Dis Assoc Disord. Jan‐Mar 2018;32(1):1‐9.