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NIH conference. Alzheimer disease: clinical and biological heterogeneity
Friedland RP, Koss E, Haxby JV, Grady CL, Luxenberg J, Schapiro MB, Kaye J.. Annals of internal medicine, 1988-08-01
Topic: Amyloid, tau and blood-test diagnosis
Plain-language summary
The clinical and biological features of Alzheimer disease are not uniform in their expression; heterogeneity is evident in the disease's clinical, anatomic, and physiologic characteristics. The presence of considerable intersubject and intrasubject heterogeneity suggests that subtypes of the disease exist. We define subtypes of Alzheimer disease in regard to the behavioral features (for example, predominant right or left hemisphere, or symmetrical impairment), inheritance (familial or sporadic), dosage of chromosome 21 (presence of the Down syndrome), time course of progression, age of onset (presenile or senile), and presence or absence of motor deficit (myoclonus or signs of an extrapyramidal syndrome). Studies of regional cerebral glucose metabolism with positron emission tomography and [18-fluorine] fluorodeoxyglucose show focal alterations in glucose use, with cerebral metabolic asymmetries in patients with Alzheimer disease that are related to the nature of the cognitive deficit. Serial roentgenographic computed tomographic studies show heterogeneous rates of lateral ventricle enlargement in the disease that are related to rates of cognitive decline. Similar anatomic and physiologic abnormalities are also found in persons 45 years of age or older who have the Down syndrome. Furthermore, patients with Alzheimer disease who have extrapyramidal dysfunction or myoclonus are a distinct subgroup, with specific abnormalities of central monoamine markers of dopamine metabolism, serotonin metabolism, and the hydroxylation cofactor, biopterin. The concept of subtypes in Alzheimer disease serves as a model with which the interactions of genetic influences with environmental factors can be examined.
What this study adds
Evidence grade: Low
This is a narrative review. This review describes that Alzheimer's disease is not uniform and that subtypes exist based on features such as inheritance, age of onset, and brain metabolism. It does not report any treatment, cure, or prevention, and notes that similar brain abnormalities are found in people 45 or older with Down syndrome.
Taken from this record’s own fields, not from reading the paper. The grade is assigned from the abstract’s wording; what that means.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
APA 7th
Friedland, R. P., Koss, E., Haxby, J. V., Grady, C. L., Luxenberg, J., Schapiro, M. B., et al. (1988). NIH conference. Alzheimer disease: clinical and biological heterogeneity. Annals of internal medicine. https://doi.org/10.7326/0003-4819-109-4-298
Vancouver
Friedland RP, Koss E, Haxby JV, Grady CL, Luxenberg J, Schapiro MB, et al. NIH conference. Alzheimer disease: clinical and biological heterogeneity. Annals of internal medicine. 1988. doi:10.7326/0003-4819-109-4-298. PMID: 2969203.
BibTeX
@article{friedland1988-2969203,
author = {Friedland, R. P. and Koss, E. and Haxby, J. V. and Grady, C. L. and Luxenberg, J. and Schapiro, M. B. and Kaye, J.},
title = {{NIH conference. Alzheimer disease: clinical and biological heterogeneity}},
journal = {Annals of internal medicine},
year = {1988},
doi = {10.7326/0003-4819-109-4-298},
pmid = {2969203},
url = {https://doi.org/10.7326/0003-4819-109-4-298}
}
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.
Key findings
- The presence of considerable intersubject and intrasubject heterogeneity suggests that subtypes of the disease exist.
Why it matters
This review describes that Alzheimer's disease is not uniform and that subtypes exist based on features such as inheritance, age of onset, and brain metabolism. It does not report any treatment, cure, or prevention, and notes that similar brain abnormalities are found in people 45 or older with Down syndrome.
Study details
- Evidence strengthLow
How this study scored 46/100
Published in a leading specialty journal. Scored zero for study design, sample size, effect reported, studied in people and randomized / blinded because the record does not state it. We have no data on senior author's track record, so that was left out: it earned 44 of the 96 points we could judge it on, which is 46 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 9 / 10 | Tier 2 — leading specialty journal (Annals of internal medicine) |
| Journal's citation record | 4 / 4 | Annals of Internal Medicine: journal h-index 648 (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 | 1988 — 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) |
| Randomized / blinded | 0 / 2 | No randomization or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 5 / 7 | Cited 101 times (OpenAlex, 2026-10-10) |
| Citations per year | 1 / 5 | 2.5 citations a year over 40 year(s) since 1988 |
| Impact for its field and year | 4 / 6 | Cited 8.2× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 2 / 6 | Cited by 3 other studies in this library |
| Still being cited | 1 / 4 | Cited 7 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | — / 4 | Senior author's record not available — left out of this score |
| Institution's track record | 3 / 3 | National Institutes of Health: institution h-index 2,723 (OpenAlex) |
| Multicenter collaboration | 1 / 3 | OpenAlex lists 2 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 2969203) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 44 / 96 | Scored on 19 of 20 parts. We have no data for the rest, so they are left out: 44 of the 96 points we could judge it on is 46 out of 100. |
| Total | 46 / 100 | — |
What each of these 20 components measures, and what this score is not →
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