This page is alzhub.org's plain-English summary of a published study, not the paper itself. It is generated from the record we hold for this study, sourced and linked below — check the original for the full text and methods.

57/100

✓ Peer-reviewed alzhub usefulness score 57 out of 100. How common it is

Topic: Risk, prevention and care in population studies

Plain-language summary

Dementia is an increasing focus for policymakers, civil organizations and multidisciplinary researchers. The most recent descriptive epidemiological research into dementia is enabling investigation into how the prevalence and incidence are changing over time. To establish clear trends, such comparisons need to be founded on population-based studies that use similar diagnostic and research methods consistently over time. This narrative Review synthesizes the findings from 14 studies that investigated trends in dementia prevalence (nine studies) and incidence (five studies) from Sweden, Spain, the UK, the Netherlands, France, the USA, Japan and Nigeria. Besides the Japanese study, these studies indicate stable or declining prevalence and incidence of dementia, and some provide evidence of sex-specific changes. No single risk or protective factor has been identified that fully explains the observed trends, but major societal changes and improvements in living conditions, education and healthcare might have favourably influenced physical, mental and cognitive health throughout an individual's life course, and could be responsible for a reduced risk of dementia in later life. Analytical epidemiological approaches combined with translational neuroscientific research could provide a unique opportunity to explore the neuropathology that underlies changing occurrence of dementia in the general population.

Cite this study APA, Vancouver, BibTeX · download .bib or .ris

APA 7th

Wu, Y. T., Beiser, A. S., Breteler, M. M. B., Fratiglioni, L., Helmer, C., Hendrie, H. C., et al. (2017). The changing prevalence and incidence of dementia over time - current evidence. Nature reviews. Neurology. https://doi.org/10.1038/nrneurol.2017.63

Vancouver

Wu YT, Beiser AS, Breteler MMB, Fratiglioni L, Helmer C, Hendrie HC, et al. The changing prevalence and incidence of dementia over time - current evidence. Nature reviews. Neurology. 2017. doi:10.1038/nrneurol.2017.63. PMID: 28497805.

BibTeX

@article{wu2017-28497805,
  author  = {Wu, Y. T. and Beiser, A. S. and Breteler, M. M. B. and Fratiglioni, L. and Helmer, C. and Hendrie, H. C. and Honda, H. and Ikram, M. A. and others},
  title   = {{The changing prevalence and incidence of dementia over time - current evidence}},
  journal = {Nature reviews. Neurology},
  year    = {2017},
  doi     = {10.1038/nrneurol.2017.63},
  pmid    = {28497805},
  url     = {https://doi.org/10.1038/nrneurol.2017.63}
}

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.

How to read this study

Design: this is a narrative review. It summarises a field without a fixed search method, so it shows how authors read the evidence rather than measuring it. Use it to find the primary studies, not as a result in itself.
Size: the record gives no participant count. Look for one in the original before trusting a pattern.
Effect: the record gives no effect size, so the summary above cannot say how large any difference was.

What the evidence grade means here

This page is graded low. alzhub.org assigns the grade automatically from keywords in the abstract, not from reading the paper. Low means the abstract matched neither pattern. It is the default label, and it does not mean the work is poor; many sound lab and imaging papers land here. It can add at most 5 of the 100 points in the study score, and it is a label about design, not a verdict on whether the findings are true.

New to reading papers? Six questions to ask of any Alzheimer’s study · how we score.

Key findings

To establish clear trends, such comparisons need to be founded on population-based studies that use similar diagnostic and research methods consistently over time.
This narrative Review synthesizes the findings from 14 studies that investigated trends in dementia prevalence (nine studies) and incidence (five studies) from Sweden, Spain, the UK, the Netherlands, France, the USA, Japan and Nigeria.
Besides the Japanese study, these studies indicate stable or declining prevalence and incidence of dementia, and some provide evidence of sex-specific changes.
No single risk or protective factor has been identified that fully explains the observed trends, but major societal changes and improvements in living conditions, education and healthcare might have favourably influenced physical, mental and cognitive health throughout an individual's life course, and could be responsible for a reduced risk of dementia in later life.
Analytical epidemiological approaches combined with translational neuroscientific research could provide a unique opportunity to explore the neuropathology that underlies changing occurrence of dementia in the general population.

Why it matters

This narrative review of 14 population studies (nine on how common dementia is, five on new cases) from Sweden, Spain, the UK, the Netherlands, France, the USA, Japan and Nigeria found that, except for the Japanese study, dementia prevalence and incidence were stable or declining, with some evidence of differences between the sexes. The authors stress that such trends are only clear when studies use the same diagnostic and research methods over time. They suggest better living conditions, education and healthcare might have lowered dementia risk, but no single factor explains the trend, and this is a hypothesis rather than a tested finding.

New to this subject? Start with our plain-English guide: Alzheimer's in numbers →

Study details

Study designnarrative review
Evidence strengthLow

How this study scored 57/100

Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomized / blinded because the record does not state it.

Component	Points	Why
Journal tier	7 / 10	Tier 3 — peer-reviewed journal (Nature reviews. Neurology)
Journal's citation record	3 / 4	Nature Reviews Neurology: journal h-index 269 (OpenAlex, 2026-10-29)
Study design	0 / 12	Design recorded as “narrative review”, which our rubric does not rank (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	2 / 5	2017 — within 10 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)
Randomized / blinded	0 / 2	No randomization or blinding stated — scores zero (not stated in the record — scored 0)
Times cited	6 / 7	Cited 777 times (OpenAlex, 2026-10-10)
Citations per year	5 / 5	70.6 citations a year over 11 year(s) since 2017
Impact for its field and year	4 / 6	Cited 13.2× the average for papers of its field and year (OpenAlex FWCI)
Cited by studies here	4 / 6	Cited by 61 other studies in this library
Still being cited	4 / 4	Cited 236 times in 2024–2026 (2026 still in progress; OpenAlex)
Senior author's track record	4 / 4	Last-listed author Carol Brayne: h-index 159 (OpenAlex, whole career)
Institution's track record	2 / 3	University of Michigan: institution h-index 2,240 (OpenAlex)
Multicenter collaboration	3 / 3	OpenAlex lists 20 institution(s) in 8 countries
Indexed in PubMed	2 / 2	Indexed in PubMed (PMID 28497805)
Free to read	0 / 2	Behind a paywall — scores zero
Total	57 / 100	—

What each of these 20 components measures, and what this score is not →

Read the original

Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).

Studies in the library that share something with this one. The line above each title says what.

Studies this one cites

Referenced by this study and also in the alzhub library, so you can read them here. Showing 12 of 23.

Later studies that cite this one

61 studies in the alzhub library list this one in their references. Showing the 8 highest-scoring.

Related studies in How common it is from nearby years

Also tagged “prevalence”

1,223 studies in the library carry the topic tag “prevalence”; these are this study's neighbours in a fixed, alphabetical-by-hash tour of them, not the closest in content. All 1,223 tagged studies.

Studies sharing this one's topic tags

Similar studies

More on How common it is

See all studies in How common it is →