Data repository · Database
ADNI
A longitudinal repository of neuroimaging, biomarker, and clinical data across Alzheimer's disease progression.
What ADNI is
The Alzheimer's Disease Neuroimaging Initiative (ADNI) is a long-term research study and data repository established to track the progression of Alzheimer's disease. Spanning multiple operational phases—ADNI-1, ADNI-GO, ADNI-2, ADNI-3, and ADNI-4—it gathers multifaceted patient records to assist researchers in tracking disease pathology from unimpaired cognitive states through mild cognitive impairment (MCI) to Alzheimer's disease and dementia.
The repository curates a broad range of biological and clinical data modalities, including structural, functional, and molecular brain imaging, biofluid biomarkers from blood and cerebrospinal fluid, genetic data, neuropathology, and cognitive assessments. These data are centralised to support clinical trial planning, scientific investigation, and educational purposes across the neurodegenerative disease research community.
How it is organised
Data collection within ADNI is governed by a Schedule of Events that specifies the assessments and procedures administered during participant visits, conditioned on factors such as clinical diagnosis (cognitively unimpaired, mild cognitive impairment, or Alzheimer's disease/dementia). Across successive phases, collection protocols encompass magnetic resonance imaging (MRI) scans alongside acquisition parameters and quality control metrics, positron emission tomography (PET), biofluid sampling, cognitive questionnaires, and remote participant monitoring in ADNI-4.
Data records are hosted and managed through the Laboratory of Neuro Imaging (LONI) Image and Data Archive (IDA). The repository distributes raw and pre-processed MRI datasets, numerical summary tables, clinical assessment scores, and biospecimen records. In addition, broader and more comprehensive genomic and omics datasets gathered through ADNI are compiled and accessed via external repositories including NIAGADS and NACC.
Key facts
- Host repository
- LONI Image and Data Archive (IDA)
- Cohort size
- 2.4k+ participants
- Study phases
- ADNI-1, ADNI-GO, ADNI-2, ADNI-3, and ADNI-4
- Participant diagnostic groups
- Cognitively unimpaired, mild cognitive impairment (MCI), Alzheimer's disease / dementia
- Primary imaging modalities
- MRI and PET
- Biofluid modalities
- CSF and blood biomarkers
- Genetic data repositories
- LONI IDA, NIAGADS, and NACC
What you can use it for
- Alzheimer's biomarker discovery
- Evaluating changes in blood and cerebrospinal fluid markers alongside brain pathology across clinical cohorts.
- Neuroimaging trajectory analysis
- Measuring structural and molecular brain alterations across longitudinal MRI and PET acquisitions to map cognitive decline.
- Clinical research planning
- Utilising historical progression rates, cognitive scores, and imaging protocols to design and power prospective clinical trials.
Strengths and limits
Good at
- Provides deeply phenotyped longitudinal tracking combining neuroimaging, biofluid biomarkers, genetics, and cognitive evaluations across multiple disease stages.
- Encompasses standardisation across scanner protocols, quality control processes, and imaging numerical datasets.
- Spans multiple continuous study phases ranging from ADNI-1 through ADNI-4 with thousands of documented participants.
Watch out for
- Data cannot be accessed programmatically via automated scripts or application programming interfaces.
- Redistribution of repository data is strictly prohibited under the mandatory Data Use Agreement.
- Full genomic and related omics datasets are not wholly self-contained and require separate access requests through external repositories such as NIAGADS or NACC.
Questions
Can I search ADNI without writing code?
ADNI is catalogued here but not yet queried live, so the agent can point you to it but cannot search it for you yet.
Can I reuse data from ADNI?
Data Use Agreement; redistribution prohibited. Not reachable from here by design. Apply through LONI. Terms: https://adni.loni.usc.edu/data-samples/access-data/
How can researchers access data held in ADNI?
Access requires an online application through the LONI Image and Data Archive specifying the investigator's institutional affiliation and research intent, alongside acceptance of the ADNI Data Use Agreement.
What types of imaging data are available?
The archive holds both MRI and PET data, including scanner protocol metadata, quality control outputs, pre-processed datasets, and numerical summary tables.
Does data access expire after approval?
Yes, user accounts require the submission of an annual update to remain active; accounts expire if an annual update is not completed in time.
Can ADNI datasets be redistributed to collaborators?
No, the ADNI Data Use Agreement explicitly forbids the redistribution of repository data.
Written from ADNI's own website and reference material. Statements citing a figure that does not appear there are removed before publication. Licence and running details come from our registry.