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The evolving roles of imaging and fluid biomarkers for Alzheimer disease over the past quarter century
Laura Ibáñez. Alzheimer s & Dementia, 2025-12-01
Topic: Amyloid, tau and blood-test diagnosis
In 2004, the first radiotracer that bound amyloid plaques was reported, which enabled visualization of the amount and regional distribution of amyloid plaques in the brains of living individuals via positron emission tomography (PET). Radiotracers binding to insoluble tau aggregates were described in 2013 and 2014. The use of amyloid and tau PET as a reference standard, as well as improvements in fluid biomarker assay technology, led to the first of many accurate AD blood tests in 2017 and 2018. These imaging and fluid biomarkers of AD have undergone waves of development, validation, and regulatory approval. AD research studies now use biomarkers extensively to study the biology of disease. Clinical trials use biomarkers to confirm that participants have AD pathology and to monitor the effects of treatment. AD biomarkers are increasingly being used in the clinical diagnosis of AD. The high acceptability and accessibility of AD blood tests may enable AD biomarker testing to become the standard of care in patients with cognitive impairment. In the future, if trials of preventative treatments are positive, AD biomarker testing of cognitively unimpaired older individuals may become routine. Advances in imaging and fluid biomarkers over the past quarter century have enabled greater understanding of AD biology and led to the successful development, approval, and clinical use of disease-modifying AD treatments that target amyloid pathology. The clinical availability of AD-specific treatments and high-accuracy AD blood tests is currently transforming the clinical diagnosis and care of patients with AD.
Key findings
- In 2004, the first radiotracer that bound amyloid plaques was reported, which enabled visualization of the amount and regional distribution of amyloid plaques in the brains of living individuals via positron emission tomography (PET).
- Radiotracers binding to insoluble tau aggregates were described in 2013 and 2014.
- The use of amyloid and tau PET as a reference standard, as well as improvements in fluid biomarker assay technology, led to the first of many accurate AD blood tests in 2017 and 2018.
- These imaging and fluid biomarkers of AD have undergone waves of development, validation, and regulatory approval.
- AD research studies now use biomarkers extensively to study the biology of disease.
Why it matters
This review describes the development of imaging and fluid biomarkers for Alzheimer's disease over the past quarter century and their use in research, trials and clinical diagnosis. It is about biomarkers and diagnosis, not treatment, and does not demonstrate any cure or prevention.
New to this subject? Start with our plain-English guide: Blood tests & biomarkers →
Study details
- Evidence strengthLow
How this study scored 32/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Alzheimer s & Dementia) |
| Journal's citation record | 2 / 4 | Alzheimer s & Dementia: journal h-index 228 (OpenAlex, 2026-10-29) |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 4 / 5 | 2025 — within 3 year(s) of the newest study here |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 0 / 7 | Cited 0 times (OpenAlex, 2026-10-10) |
| Citations per year | 0 / 5 | 0.0 citations a year over 3 year(s) since 2025 |
| Impact for its field and year | 0 / 6 | Cited 0.0× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 0 / 4 | Cited 0 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Laura Ibáñez: h-index 37 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | Washington University in St. Louis: institution h-index 1,962 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 41447680) |
| Free to read | 2 / 2 | Free to read |
| Total | 32 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
- DOI: 10.1002/alz70856_101336
- PubMed: 41447680
- Original source →
- Free full text: Alzheimer s & Dementia →
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Ibáñez, L. (2025). The evolving roles of imaging and fluid biomarkers for Alzheimer disease over the past quarter century. Alzheimer s & Dementia. https://doi.org/10.1002/alz70856_101336
Vancouver
Ibáñez L. The evolving roles of imaging and fluid biomarkers for Alzheimer disease over the past quarter century. Alzheimer s & Dementia. 2025. doi:10.1002/alz70856_101336. PMID: 41447680.
BibTeX
@article{ibanez2025-41447680,
author = {Ibáñez, Laura},
title = {{The evolving roles of imaging and fluid biomarkers for Alzheimer disease over the past quarter century}},
journal = {Alzheimer s \& Dementia},
year = {2025},
doi = {10.1002/alz70856_101336},
pmid = {41447680},
url = {https://doi.org/10.1002/alz70856_101336}
}