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A population-based study of dementia in 85-year-olds
Skoog I, Nilsson L, Palmertz B, Andreasson LA, Svanborg A.. The New England journal of medicine, 1993-01-01
Topic: Risk, prevention and care in population studies
Background The aim of this study was to investigate the causes, severity, and prevalence of dementia in a representative sample of 494 85-year-olds living in Gothenburg, Sweden. Methods The study included a psychiatric interview, neuropsychological and physical examinations, comprehensive laboratory tests, electrocardiography, chest radiography, computed tomography (CT) of the head, and analysis of cerebrospinal fluid. A person close to each subject was also interviewed. Dementia was defined according to the criteria proposed in the Diagnostic and Statistical Manual of Mental Disorders (third edition, revised), Alzheimer's disease according to the criteria of the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association, and vascular dementia according to recently proposed criteria that incorporate information from CT scanning and the patient's neurologic history. Results The prevalence of dementia was 29.8 percent (147 subjects). The condition was mild in 8.3 percent, moderate in 10.3 percent, and severe in 11.1 percent. There were no significant sex-related differences in prevalence or severity. Of the subjects with dementia, 43.5 percent had Alzheimer's disease, 46.9 percent had vascular dementia (multi-infarct dementia in 34.6 percent, dementia related to cerebral hypoperfusion in 4.1 percent, and mixed dementia in 8.2 percent), and 9.5 percent had dementia due to other causes. The three-year mortality rate was 23.1 percent in the subjects without dementia, 42.2 percent in the patients with Alzheimer's disease, and 66.7 percent in the patients with vascular dementia. Infarcts detected by CT scanning were significantly more common in the subjects with dementia than in those without it (27.9 percent vs. 12.6 percent). Conclusions Dementia was present in nearly a third of unselected 85-year-olds in Sweden. Almost half these subjects appeared to have vascular dementia, which may currently be more amenable to prevention or treatment than Alzheimer's disease.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
APA 7th
Skoog, I., Nilsson, L., Palmertz, B., Andreasson, L. A., & Svanborg, A. (1993). A population-based study of dementia in 85-year-olds. The New England journal of medicine. https://doi.org/10.1056/nejm199301213280301
Vancouver
Skoog I, Nilsson L, Palmertz B, Andreasson LA, Svanborg A. A population-based study of dementia in 85-year-olds. The New England journal of medicine. 1993. doi:10.1056/nejm199301213280301. PMID: 8417380.
BibTeX
@article{skoog1993-8417380,
author = {Skoog, I. and Nilsson, L. and Palmertz, B. and Andreasson, L. A. and Svanborg, A.},
title = {{A population-based study of dementia in 85-year-olds}},
journal = {The New England journal of medicine},
year = {1993},
doi = {10.1056/nejm199301213280301},
pmid = {8417380},
url = {https://doi.org/10.1056/nejm199301213280301}
}
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.
Key findings
- Results The prevalence of dementia was 29.8 percent (147 subjects).
- There were no significant sex-related differences in prevalence or severity.
- Infarcts detected by CT scanning were significantly more common in the subjects with dementia than in those without it (27.9 percent vs. 12.6 percent).
Why it matters
Of 494 85-year-olds examined in Gothenburg, Sweden, 29.8% had dementia (8.3% mild, 10.3% moderate, 11.1% severe), with no significant difference between men and women. Using CT-informed criteria, 46.9% of cases were classed as vascular dementia and 43.5% as Alzheimer's disease, and three-year death rates were 66.7% and 42.2% respectively versus 23.1% in those without dementia. This is a one-city snapshot that tested no treatment; the authors' suggestion that vascular dementia "may currently be more amenable to prevention or treatment" is a hypothesis, not a finding.
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Study details
- Participants147
- Evidence strengthLow
How this study scored 55/100
Published in a top-tier journal. Scored zero for study design, effect reported and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 10 / 10 | Tier 1 — top-tier general journal (The New England journal of medicine) |
| Journal's citation record | 4 / 4 | New England Journal of Medicine: journal h-index 1,505 (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 | 1993 — older than 20 years, still counted |
| Sample size | 2 / 4 | 147 participants |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| 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 | 6 / 7 | Cited 697 times (OpenAlex, 2026-10-10) |
| Citations per year | 3 / 5 | 19.9 citations a year over 35 year(s) since 1993 |
| Impact for its field and year | 5 / 6 | Cited 33.0× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 29 other studies in this library |
| Still being cited | 1 / 4 | Cited 8 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Alvar Svanborg: h-index 43 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | University of Illinois Chicago: institution h-index 918 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 2 institution(s) in 2 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 8417380) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 55 / 100 | — |
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Read the original
- DOI: 10.1056/nejm199301213280301
- PubMed: 8417380
- Original source →
- Free full text: New England Journal of Medicine →
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
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