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43/100

✓ Peer-reviewed alzhub usefulness score 43 out of 100. Risk genes beyond APOE

Topic: Amyloid, tau and blood-test diagnosis

Plain-language summary

Plasma and serum biochemical markers proposed for Alzheimer disease (AD) are based on pathophysiologic processes such as amyloid plaque formation [amyloid beta-protein (A beta), A beta autoantibodies, platelet amyloid precursor protein (APP) isoforms], inflammation (cytokines), oxidative stress (vitamin E, isoprostanes), lipid metabolism (apolipoprotein E, 24S-hydroxycholesterol), and vascular disease [homocysteine, lipoprotein (a)]. Most proteins or metabolites evaluated in plasma or serum thus far are, at best, biological correlates of AD: levels are statistically different in AD versus controls in some cohorts, but they lack sensitivity or specificity for diagnosis or for tracking response to therapy. Approaches combining panels of existing biomarkers or surveying the range of proteins in plasma (proteomics) show promise for discovering biomarker profiles that are characteristic of AD

What this study adds

Evidence grade: Low

This is a narrative review. This review concludes that most proteins or metabolites measured in plasma or serum so far are at best biological correlates of Alzheimer's disease and lack the sensitivity or specificity needed for diagnosis or for tracking response to therapy. It notes that combining panels of markers or using proteomics may help discover useful profiles, but no such test is established.

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

Irizarry, M. C. (2004). Biomarkers of Alzheimer disease in plasma. NeuroRx : the journal of the American Society for Experimental NeuroTherapeutics. https://doi.org/10.1602/neurorx.1.2.226

Vancouver

Irizarry MC. Biomarkers of Alzheimer disease in plasma. NeuroRx : the journal of the American Society for Experimental NeuroTherapeutics. 2004. doi:10.1602/neurorx.1.2.226. PMID: 15717023.

BibTeX

@article{irizarry2004-15717023,
  author  = {Irizarry, M. C.},
  title   = {{Biomarkers of Alzheimer disease in plasma}},
  journal = {NeuroRx : the journal of the American Society for Experimental NeuroTherapeutics},
  year    = {2004},
  doi     = {10.1602/neurorx.1.2.226},
  pmid    = {15717023},
  url     = {https://doi.org/10.1602/neurorx.1.2.226}
}

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.

How to read this study

Design: this is a narrative review. It summarises a field without a fixed search method, so it shows how authors read the evidence rather than measuring it. Use it to find the primary studies, not as a result in itself.
Size: the record gives no participant count. Look for one in the original before trusting a pattern.
Effect: the record gives no effect size, so the summary above cannot say how large any difference was.

What the evidence grade means here

This page is graded low. alzhub.org assigns the grade automatically from keywords in the abstract, not from reading the paper. Low means the abstract matched neither pattern. It is the default label, and it does not mean the work is poor; many sound lab and imaging papers land here. It can add at most 5 of the 100 points in the study score, and it is a label about design, not a verdict on whether the findings are true.

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Key findings

Most proteins or metabolites evaluated in plasma or serum thus far are, at best, biological correlates of AD: levels are statistically different in AD versus controls in some cohorts, but they lack sensitivity or specificity for diagnosis or for tracking response to therapy.
Approaches combining panels of existing biomarkers or surveying the range of proteins in plasma (proteomics) show promise for discovering biomarker profiles that are characteristic of AD, yet distinct from nondemented patients or patients with other forms of dementia.

Why it matters

This review concludes that most proteins or metabolites measured in plasma or serum so far are at best biological correlates of Alzheimer's disease and lack the sensitivity or specificity needed for diagnosis or for tracking response to therapy. It notes that combining panels of markers or using proteomics may help discover useful profiles, but no such test is established.

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Study details

Evidence strengthLow

How this study scored 43/100

Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomized / blinded because the record does not state it.

Component	Points	Why
Journal tier	7 / 10	Tier 3 — peer-reviewed journal (NeuroRx : the journal of the American Society for Experimental NeuroTherapeutics)
Journal's citation record	1 / 4	NeuroRx: journal h-index 78 (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	2004 — 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 269 times (OpenAlex, 2026-10-10)
Citations per year	3 / 5	11.2 citations a year over 24 year(s) since 2004
Impact for its field and year	4 / 6	Cited 8.5× the average for papers of its field and year (OpenAlex FWCI)
Cited by studies here	3 / 6	Cited by 12 other studies in this library
Still being cited	1 / 4	Cited 12 times in 2024–2026 (2026 still in progress; OpenAlex)
Senior author's track record	3 / 4	Last-listed author Michael C. Irizarry: h-index 65 (OpenAlex, whole career)
Institution's track record	2 / 3	Massachusetts General Hospital: institution h-index 2,057 (OpenAlex)
Multicenter 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 15717023)
Free to read	0 / 2	Behind a paywall — scores zero
Total	43 / 100	—

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