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The prevalence and causes of dementia in people under the age of 65 years
Harvey RJ, Skelton-Robinson M, Rossor MN.. Journal of neurology, neurosurgery, and psychiatry, 2003-09-01
Topic: Risk, prevention and care in population studies
Objectives To determine the prevalence of dementia in people under the age of 65 in a large catchment area, and use these figures to estimate the number of younger people affected by dementia in the UK. Design Epidemiological catchment area prevalence survey. Setting The London boroughs of Kensington and Chelsea, Westminster, and Hillingdon with a total population of 567500 people. Participants All residents of the catchment area with dementia, where the illness began before the age of 65 years. Participants were notified to the study by medical and care professionals. The diagnosis and age of onset was established from all available health and social care records. In total, 227 people were identified, of whom 185 fulfilled the inclusion criteria of having a dementia which started before their 65th birthday. Main outcome measures Diagnosis of dementia and differential diagnosis of the cause of the dementia. Results The prevalence of dementia in those aged 30-64 was 54.0 per 100000 (95% CI 45.1 to 64.1 per 100000). For those aged 45-64 years, the prevalence was 98.1 per 100000 (95% CI 81.1 to 118.0 per 100000). From the age of 35 onwards, the prevalence of dementia approximately doubled with each 5 year increase in age. Extrapolating these figures nationally suggests that there are 18319 (15296-21758) people with dementia under the age of 65 in the UK. Conclusions The study confirms previous "guestimates" of the number of younger people affected by dementia in UK. The prevalence figures generated are robust, and are supported by other smaller and targeted prevalence surveys. The prevalence figures provided by this study will allow health planners to accurately estimate need and plan services.
Key findings
- Results The prevalence of dementia in those aged 30-64 was 54.0 per 100000 (95% CI 45.1 to 64.1 per 100000).
- Extrapolating these figures nationally suggests that there are 18319 (15296-21758) people with dementia under the age of 65 in the UK.
Why it matters
In three London boroughs (population 567,500), this 2003 survey found 185 people whose dementia began before age 65. That works out to 54.0 per 100,000 people aged 30–64 and 98.1 per 100,000 aged 45–64, with the rate roughly doubling every 5 years from age 35. Extrapolated to the UK, the authors estimated about 18,319 people under 65 with dementia (range 15,296–21,758), a figure they intended for planning services. Cases were counted only if professionals reported them, and the study tests no treatment or prevention.
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Study details
- Participants567,500
- Evidence strengthLow
How this study scored 56/100
Published in a peer-reviewed journal. Scored zero for study design, effect reported and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Journal of neurology, neurosurgery, and psychiatry) |
| Journal's citation record | 3 / 4 | Journal of Neurology Neurosurgery & Psychiatry: journal h-index 336 (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 | 2003 — older than 20 years, still counted |
| Sample size | 4 / 4 | 567,500 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 649 times (OpenAlex, 2026-10-10) |
| Citations per year | 4 / 5 | 26.0 citations a year over 25 year(s) since 2003 |
| Impact for its field and year | 3 / 6 | Cited 6.1× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 4 / 6 | Cited by 37 other studies in this library |
| Still being cited | 3 / 4 | Cited 60 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Richard J. Harvey: h-index 26 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | Imperial College London: institution h-index 1,744 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 3 institution(s) in 2 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 12933919) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 56 / 100 | — |
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Read the original
- DOI: 10.1136/jnnp.74.9.1206
- PubMed: 12933919
- Original source →
- Free full text: Journal of Neurology Neurosurgery & Psychiatry →
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
Harvey, R. J., Skelton-Robinson, M., & Rossor, M. N. (2003). The prevalence and causes of dementia in people under the age of 65 years. Journal of neurology, neurosurgery, and psychiatry. https://doi.org/10.1136/jnnp.74.9.1206
Vancouver
Harvey RJ, Skelton-Robinson M, Rossor MN. The prevalence and causes of dementia in people under the age of 65 years. Journal of neurology, neurosurgery, and psychiatry. 2003. doi:10.1136/jnnp.74.9.1206. PMID: 12933919.
BibTeX
@article{harvey2003-12933919,
author = {Harvey, R. J. and Skelton-Robinson, M. and Rossor, M. N.},
title = {{The prevalence and causes of dementia in people under the age of 65 years}},
journal = {Journal of neurology, neurosurgery, and psychiatry},
year = {2003},
doi = {10.1136/jnnp.74.9.1206},
pmid = {12933919},
url = {https://doi.org/10.1136/jnnp.74.9.1206}
}
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