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Ecology of the aging human brain
Sonnen JA, Santa Cruz K, Hemmy LS, Woltjer R, Leverenz JB, Montine KS, Jack CR, Kaye J et al.. Archives of neurology, 2011-08-01
Topic: Risk, prevention and care in population studies
Background Alzheimer disease, cerebral vascular brain injury, and isocortical Lewy body disease (LBD) are the major contributors to dementia in community- and population-based studies. Objective To estimate the prevalence of clinically silent forms of these diseases in cognitively normal (CN) adults. Design Autopsy study. Setting Community- and population based. Participants A total of 1672 brain autopsies from the Adult Changes in Thought study, Honolulu-Asia Aging Study, Nun Study, and Oregon Brain Aging Study, of which 424 met the criteria for CN. Main outcome measures Of these, 336 cases had a comprehensive neuropathologic examination of neuritic plaque density, Braak stage for neurofibrillary tangles, LB distribution, and number of cerebral microinfarcts. Results Forty-seven percent of CN cases had moderate or frequent neuritic plaque density; of these, 6% also had Braak stage V or VI for neurofibrillary tangles. Fifteen percent of CN cases had medullary LBD; 8% also had nigral and 4% isocortical LBD. The presence of any cerebral microinfarcts was identified in 33% and of high-level cerebral microinfarcts in 10% of CN individuals. Overall, the burden of lesions in each individual and their comorbidity varied widely within each study but were similar across studies. Conclusions These data show an individually varying complex convergence of subclinical diseases in the brain of older CN adults. Appreciating this ecology should help guide future biomarker and neuroimaging studies and clinical trials that focus on community- and population-based cohorts.
Key findings
- Results Forty-seven percent of CN cases had moderate or frequent neuritic plaque density; of these, 6% also had Braak stage V or VI for neurofibrillary tangles.
- Overall, the burden of lesions in each individual and their comorbidity varied widely within each study but were similar across studies.
Why it matters
In 424 cognitively normal adults who had brain autopsies, 47% had moderate or frequent neuritic plaque density and 33% had cerebral microinfarcts. This shows that Alzheimer's-related brain changes and other lesions are common in people who were cognitively normal, and the burden varied widely between individuals.
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Study details
- Participants1,672
- Evidence strengthLow
How this study scored 52/100
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 (Archives of neurology) |
| Journal's citation record | 3 / 4 | Archives of Neurology: journal h-index 353 (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 | 2011 — within 20 year(s) of the newest study here |
| Sample size | 3 / 4 | 1,672 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 | 5 / 7 | Cited 174 times (OpenAlex, 2026-10-10) |
| Citations per year | 3 / 5 | 10.2 citations a year over 17 year(s) since 2011 |
| Impact for its field and year | 4 / 6 | Cited 9.1× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 20 other studies in this library |
| Still being cited | 2 / 4 | Cited 15 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Joshua Aaron Sonnen: h-index 49 (OpenAlex, whole career) |
| Institution's track record | 3 / 3 | University of Washington: institution h-index 3,540 (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 21825242) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 52 / 100 | — |
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Read the original
- DOI: 10.1001/archneurol.2011.157
- PubMed: 21825242
- Original source →
- Free full text: PubMed Central →
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. 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
Sonnen, J. A., Santa Cruz, K., Hemmy, L. S., Woltjer, R., Leverenz, J. B., Montine, K. S., et al. (2011). Ecology of the aging human brain. Archives of neurology. https://doi.org/10.1001/archneurol.2011.157
Vancouver
Sonnen JA, Santa Cruz K, Hemmy LS, Woltjer R, Leverenz JB, Montine KS, et al. Ecology of the aging human brain. Archives of neurology. 2011. doi:10.1001/archneurol.2011.157. PMID: 21825242.
BibTeX
@article{sonnen2011-21825242,
author = {Sonnen, J. A. and Santa Cruz, K. and Hemmy, L. S. and Woltjer, R. and Leverenz, J. B. and Montine, K. S. and Jack, C. R. and Kaye, J. and others},
title = {{Ecology of the aging human brain}},
journal = {Archives of neurology},
year = {2011},
doi = {10.1001/archneurol.2011.157},
pmid = {21825242},
url = {https://doi.org/10.1001/archneurol.2011.157}
}
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