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Focal cortical presentations of Alzheimer's disease
Alladi S, Xuereb J, Bak T, Nestor P, Knibb J, Patterson K, Hodges JR.. Brain : a journal of neurology, 2007-10-01
Topic: Amyloid, tau and blood-test diagnosis
To determine the frequency of Alzheimer's disease (AD) pathology in patients presenting with progressive focal cortical syndromes, notably posterior cortical atrophy (PCA), corticobasal syndrome (CBS), behavioural variant frontotemporal dementia (bvFTD), progressive non-fluent aphasia (PNFA) (or a mixed aphasia) and semantic dementia (SD); and to compare the age of onset, evolution and prognosis in patients with focal cortical presentations of AD versus more typical AD and those with non AD pathology. From a total of 200 patients with comprehensive prospective clinical and pathological data we selected 120 : 100 consecutive cases with focal cortical syndromes and 20 with clinically typical AD. Clinical files were reviewed blind to pathological diagnosis. Of the 100 patients with focal syndromes, 34 had AD as the primary pathological diagnosis with the following distribution across clinical subtypes: all 7 of the PCA (100%); 6 of 12 with CBS (50%); 2 of 28 with bvFTD (7.1%); 12 of 26 with PNFA (44.1%); 5 of 7 with mixed aphasia (71.4%) and 2 of 20 with SD (10%). Of 20 with clinically typical AD, 19 had pathological AD. Age at both onset and death was greater in the atypical AD cases than those with non-AD pathology, although survival was equivalent. AD is a much commoner cause of focal cortical syndromes than previously recognised, particularly in PCA, PNFA and CBS, but rarely causes SD or bvFTD. The focal syndrome may remain pure for many years. Patients with atypical AD tend to be older than those with non-AD pathology.
Key findings
- To determine the frequency of Alzheimer's disease (AD) pathology in patients presenting with progressive focal cortical syndromes, notably posterior cortical atrophy (PCA), corticobasal syndrome (CBS), behavioural variant frontotemporal dementia (bvFTD), progressive non-fluent aphasia (PNFA) (or a mixed aphasia) and semantic dementia (SD); and to compare the age of onset, evolution and prognosis in patients with focal cortical presentations of AD versus more typical AD and those with non AD pathology.
Why it matters
This study of brain tissue found that Alzheimer's disease was a much more common cause of focal cortical syndromes than previously recognized, especially in posterior cortical atrophy, progressive non-fluent aphasia and corticobasal syndrome. It is about diagnosis and disease frequency, not about treating or preventing Alzheimer's disease.
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Study details
- Participants200
- Effect size7.1%; 44.1%; 71.4%
- Evidence strengthLow
How this study scored 58/100
Published in a leading specialty journal. Scored zero for study design and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 9 / 10 | Tier 2 — leading specialty journal (Brain : a journal of neurology) |
| Journal's citation record | 4 / 4 | Brain: journal h-index 503 (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 | 2007 — within 20 year(s) of the newest study here |
| Sample size | 2 / 4 | 200 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 | 6 / 7 | Cited 587 times (OpenAlex, 2026-10-10) |
| Citations per year | 4 / 5 | 28.0 citations a year over 21 year(s) since 2007 |
| Impact for its field and year | 4 / 6 | Cited 13.7× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 4 / 6 | Cited by 51 other studies in this library |
| Still being cited | 2 / 4 | Cited 46 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author J. R. Hodges: h-index 49 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | Addenbrooke's Hospital: institution h-index 1,025 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 2 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 17898010) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 58 / 100 | — |
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Read the original
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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 names 7 authors; APA and Vancouver show the first six, BibTeX and the downloads carry all of them. Check the citation against the original before you use it.
APA 7th
Alladi, S., Xuereb, J., Bak, T., Nestor, P., Knibb, J., Patterson, K., et al. (2007). Focal cortical presentations of Alzheimer's disease. Brain : a journal of neurology. https://doi.org/10.1093/brain/awm213
Vancouver
Alladi S, Xuereb J, Bak T, Nestor P, Knibb J, Patterson K, et al. Focal cortical presentations of Alzheimer's disease. Brain : a journal of neurology. 2007. doi:10.1093/brain/awm213. PMID: 17898010.
BibTeX
@article{alladi2007-17898010,
author = {Alladi, S. and Xuereb, J. and Bak, T. and Nestor, P. and Knibb, J. and Patterson, K. and Hodges, JR.},
title = {{Focal cortical presentations of Alzheimer's disease}},
journal = {Brain : a journal of neurology},
year = {2007},
doi = {10.1093/brain/awm213},
pmid = {17898010},
url = {https://doi.org/10.1093/brain/awm213}
}
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