Home › Research › Disparities
Multicentre population-based dementia prevalence survey in Japan: a preliminary report
Ikejima C, Hisanaga A, Meguro K, Yamada T, Ouma S, Kawamuro Y, Hyouki K, Nakashima K et al.. Psychogeriatrics : the official journal of the Japanese Psychogeriatric Society, 2012-06-01
Topic: Risk, prevention and care in population studies
Community-based surveys were performed in seven rural areas in Japan to investigate the prevalence of dementia and illnesses causing dementia. A total of 5431 elderly subjects were selected based on census data from 1 October 2009. In total, 3394 participants were examined (participation rate: 62.5%), and 768 dementia cases and 529 mild cognitive impairment cases were identified. Of the illnesses causing dementia, Alzheimer's disease was the most frequent (67.4%), followed by vascular dementia (18.9%), dementia with Lewy body disease (4.6%), mixed dementia (4.2%) and other illnesses. The prevalence of dementia according to 5-year age strata between 65 and 99 years was 5.8-77.7% among the participants. The prevalence of dementia in this study was higher than in previous reports in Japan and other countries. To verify the upward trend of dementia prevalence and its background factors, we have scheduled surveys for three other urban areas in 2011-2012.
Key findings
- In total, 3394 participants were examined (participation rate: 62.5%), and 768 dementia cases and 529 mild cognitive impairment cases were identified.
- Of the illnesses causing dementia, Alzheimer's disease was the most frequent (67.4%), followed by vascular dementia (18.9%), dementia with Lewy body disease (4.6%), mixed dementia (4.2%) and other illnesses.
- The prevalence of dementia according to 5-year age strata between 65 and 99 years was 5.8-77.7% among the participants.
- The prevalence of dementia in this study was higher than in previous reports in Japan and other countries.
- To verify the upward trend of dementia prevalence and its background factors, we have scheduled surveys for three other urban areas in 2011-2012.
Why it matters
This preliminary population survey in Japan found that Alzheimer's disease was the most frequent illness causing dementia and reported a prevalence of dementia higher than in previous reports. It describes how common dementia is, not how to treat, cure, or prevent Alzheimer's disease.
New to this subject? Start with our plain-English guide: Disparities →
Study details
- Participants3,394
- Effect size62.5%; 67.4%; 18.9%
- Evidence strengthLow
How this study scored 45/100
Published in a peer-reviewed journal. Scored zero for study design and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Psychogeriatrics : the official journal of the Japanese Psychogeriatric Society) |
| Journal's citation record | 0 / 4 | Psychogeriatrics: journal h-index 62 (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 | 1 / 5 | 2012 — within 20 year(s) of the newest study here |
| Sample size | 3 / 4 | 3,394 participants |
| Effect reported | 2 / 3 | Effect reported as a number, without an interval or test |
| Studied in people | 3 / 3 | Studied in people (participant count stated) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 4 / 7 | Cited 94 times (OpenAlex, 2026-10-10) |
| Citations per year | 2 / 5 | 5.9 citations a year over 16 year(s) since 2012 |
| Impact for its field and year | 3 / 6 | Cited 3.7× 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 | 2 / 4 | Cited 16 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Takashi Asada: h-index 26 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | Tohoku University: institution h-index 880 (OpenAlex) |
| Multi-centre collaboration | 2 / 3 | OpenAlex lists 6 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 22712646) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 45 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
May need a subscription OpenAlex found no free copy of the full text (checked 6 Feb 1020), so the publisher may charge for it. The PubMed abstract is free.
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
Ikejima, C., Hisanaga, A., Meguro, K., Yamada, T., Ouma, S., Kawamuro, Y., et al. (2012). Multicentre population-based dementia prevalence survey in Japan: a preliminary report. Psychogeriatrics : the official journal of the Japanese Psychogeriatric Society. https://doi.org/10.1111/j.1479-8301.2012.00415.x
Vancouver
Ikejima C, Hisanaga A, Meguro K, Yamada T, Ouma S, Kawamuro Y, et al. Multicentre population-based dementia prevalence survey in Japan: a preliminary report. Psychogeriatrics : the official journal of the Japanese Psychogeriatric Society. 2012. doi:10.1111/j.1479-8301.2012.00415.x. PMID: 22712646.
BibTeX
@article{ikejima2012-22712646,
author = {Ikejima, C. and Hisanaga, A. and Meguro, K. and Yamada, T. and Ouma, S. and Kawamuro, Y. and Hyouki, K. and Nakashima, K. and others},
title = {{Multicentre population-based dementia prevalence survey in Japan: a preliminary report}},
journal = {Psychogeriatrics : the official journal of the Japanese Psychogeriatric Society},
year = {2012},
doi = {10.1111/j.1479-8301.2012.00415.x},
pmid = {22712646},
url = {https://doi.org/10.1111/j.1479-8301.2012.00415.x}
}
Studies this one cites
Referenced by this study and also in the alzhub library, so you can read them here.
Related studies in Disparities
Also tagged “prevalence”
1,224 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 1,224 tagged studies.