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Global estimates on the number of persons across the Alzheimer's disease continuum
Gustavsson A, Norton N, Fast T, Frölich L, Georges J, Holzapfel D, Kirabali T, Krolak-Salmon P et al.. Alzheimer's & dementia : the journal of the Alzheimer's Association, 2022-06-02
Topic: Amyloid, tau and blood-test diagnosis
Introduction Global estimates on numbers of persons in early stages of Alzheimer's disease (AD), including prodromal and preclinical, are lacking, yet are needed to inform policy decisions on preventive measures and planning for future therapies targeting AD pathology. Methods We synthesized the literature on prevalence across the AD continuum and derived a model estimating the number of persons, stratified by 5-year age groups, sex, and disease stage (AD dementia, prodromal AD, and preclinical AD). Results The global number of persons with AD dementia, prodromal AD, and preclinical AD were estimated at 32, 69, and 315 million, respectively. Together they constituted 416 million across the AD continuum, or 22% of all persons aged 50 and above. Discussion Considering predementia stages, the number of persons with AD is much larger than conveyed in available literature. Our estimates are uncertain, especially for predementia stages in low- and middle-income regions where biomarker studies are missing.
Key findings
- Results The global number of persons with AD dementia, prodromal AD, and preclinical AD were estimated at 32, 69, and 315 million, respectively.
Why it matters
By combining published prevalence studies in a model, this study estimated that worldwide about 32 million people have Alzheimer's dementia, 69 million are in the prodromal stage and 315 million in the preclinical stage — "416 million across the AD continuum, or 22% of all persons aged 50 and above". Most of these people do not have dementia, so the authors conclude the number of people with AD "is much larger than conveyed in available literature". The authors call the estimates "uncertain, especially for predementia stages in low- and middle-income regions where biomarker studies are missing"; the study counts people for planning and does not test any treatment, prevention or the risk of progressing to dementia.
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Study details
- Evidence strengthLow
How this study scored 60/100
Published in a leading specialty 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 | 9 / 10 | Tier 2 — leading specialty journal (Alzheimer's & dementia : the journal of the Alzheimer's Association) |
| 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 | 3 / 5 | 2023 — within 6 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 | 6 / 7 | Cited 888 times (OpenAlex, 2026-10-10) |
| Citations per year | 5 / 5 | 177.6 citations a year over 5 year(s) since 2023 |
| Impact for its field and year | 6 / 6 | Cited 101.8× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 4 / 6 | Cited by 39 other studies in this library |
| Still being cited | 4 / 4 | Cited 756 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author Wiesje M. van der Flier: h-index 132 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | Karolinska Institutet: institution h-index 1,477 (OpenAlex) |
| Multi-centre collaboration | 3 / 3 | OpenAlex lists 15 institution(s) in 7 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 35652476) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 60 / 100 | — |
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Read the original
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. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.
APA 7th
Gustavsson, A., Norton, N., Fast, T., Frölich, L., Georges, J., Holzapfel, D., et al. (2023). Global estimates on the number of persons across the Alzheimer's disease continuum. Alzheimer's & dementia : the journal of the Alzheimer's Association. https://doi.org/10.1002/alz.12694
Vancouver
Gustavsson A, Norton N, Fast T, Frölich L, Georges J, Holzapfel D, et al. Global estimates on the number of persons across the Alzheimer's disease continuum. Alzheimer's & dementia : the journal of the Alzheimer's Association. 2023. doi:10.1002/alz.12694. PMID: 35652476.
BibTeX
@article{gustavsson2023-35652476,
author = {Gustavsson, A. and Norton, N. and Fast, T. and Frölich, L. and Georges, J. and Holzapfel, D. and Kirabali, T. and Krolak-Salmon, P. and others},
title = {{Global estimates on the number of persons across the Alzheimer's disease continuum}},
journal = {Alzheimer's \& dementia : the journal of the Alzheimer's Association},
year = {2023},
doi = {10.1002/alz.12694},
pmid = {35652476},
url = {https://doi.org/10.1002/alz.12694}
}
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