Home › Research › Down syndrome and Alzheimer's
Down syndrome, Alzheimer's disease and seizures
Menéndez M.. Brain & development, 2005-06-01
Topic: Amyloid, tau and blood-test diagnosis
Neuropathologically, Alzheimer-type abnormalities are demonstrated in patients with Down syndrome (DS), both demented and nondemented and more than a half of patients with DS above 50 years develop Alzheimer's disease (AD). The apolipoprotein E epsilon4 allele, oestrogen deficiency, high levels of Abeta1-42 peptide, elevated expression of BACE2, and valine polymorphism of prion protein gene are associated with earlier onset of dementia in DS individuals. Advanced AD alone may be an important risk factor for new-onset seizures in older adults and age above 60 years is a recognized risk factor for poor outcome from convulsive and nonconvulsive status epilepticus. DS patients aged over 45 years are significantly more likely to develop Alzheimer's disease than those less than 45 years and up to 84% demented individuals with DS develop seizures. Late-onset epilepsy in DS is associated with AD, while early-onset epilepsy is associated with an absence of dementia. In AD patients with a younger age of dementia onset are particularly susceptible to seizures. DS adults with epilepsy score significantly higher overall on the adaptive behaviour profile. Language function declined significantly more rapidly in AD patients with seizures and there is a good correlation between the severity of EEG abnormalities and cognitive impairment whereas in DS slowing of the dominant occipital rhythm is related to AD and the frequency of the dominant occipital activity decreases at the onset of cognitive deterioration.
Key findings
- Neuropathologically, Alzheimer-type abnormalities are demonstrated in patients with Down syndrome (DS), both demented and nondemented and more than a half of patients with DS above 50 years develop Alzheimer's disease (AD).
- The apolipoprotein E epsilon4 allele, oestrogen deficiency, high levels of Abeta1-42 peptide, elevated expression of BACE2, and valine polymorphism of prion protein gene are associated with earlier onset of dementia in DS individuals.
- DS patients aged over 45 years are significantly more likely to develop Alzheimer's disease than those less than 45 years and up to 84% demented individuals with DS develop seizures.
- Late-onset epilepsy in DS is associated with AD, while early-onset epilepsy is associated with an absence of dementia.
- DS adults with epilepsy score significantly higher overall on the adaptive behaviour profile.
Why it matters
This review describes that more than half of people with Down syndrome above 50 develop Alzheimer's disease and that up to 84% of demented individuals with Down syndrome develop seizures, with late-onset epilepsy associated with Alzheimer's disease. It discusses risk factors and clinical associations but reports no treatment, cure or prevention.
Study details
- Evidence strengthLow
How this study scored 40/100
Published in a peer-reviewed 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 | 7 / 10 | Tier 3 — peer-reviewed journal (Brain & development) |
| Journal's citation record | 1 / 4 | Brain and Development: journal h-index 120 (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 | 2005 — older than 20 years, still counted |
| 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 | 5 / 7 | Cited 186 times (OpenAlex, 2026-10-10) |
| Citations per year | 3 / 5 | 8.1 citations a year over 23 year(s) since 2005 |
| Impact for its field and year | 4 / 6 | Cited 8.1× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 13 other studies in this library |
| Still being cited | 1 / 4 | Cited 13 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Manuel Menéndez‐González: h-index 44 (OpenAlex, whole career) |
| Institution's track record | 0 / 3 | Hospital Universitario Central de Asturias: institution h-index 271 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 15862185) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 40 / 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. Check the citation against the original before you use it.
APA 7th
Menéndez, M. (2005). Down syndrome, Alzheimer's disease and seizures. Brain & development. https://doi.org/10.1016/j.braindev.2004.07.008
Vancouver
Menéndez M. Down syndrome, Alzheimer's disease and seizures. Brain & development. 2005. doi:10.1016/j.braindev.2004.07.008. PMID: 15862185.
BibTeX
@article{menendez2005-15862185,
author = {Menéndez, M.},
title = {{Down syndrome, Alzheimer's disease and seizures}},
journal = {Brain \& development},
year = {2005},
doi = {10.1016/j.braindev.2004.07.008},
pmid = {15862185},
url = {https://doi.org/10.1016/j.braindev.2004.07.008}
}
Studies this one cites
Referenced by this study and also in the alzhub library, so you can read them here.
Later studies that cite this one
13 studies in the alzhub library list this one in their references. Showing the 8 highest-scoring.
Related studies in Down syndrome and Alzheimer's
Also tagged “down”
527 studies in the library carry the topic tag “down”; these are this study's neighbours in a fixed, alphabetical-by-hash tour of them, not the closest in content. All 527 tagged studies.