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51/100

✓ Peer-reviewed alzhub usefulness score 51 out of 100. Long-term cohort studies

Topic: Amyloid, tau and blood-test diagnosis

Plain-language summary

Background Identifying biomarkers associated with Alzheimer's disease (AD) progression may enable patient enrichment and improve clinical trial designs. Epigenome-wide association studies have revealed correlations between DNA methylation at cytosine-phosphate-guanine (CpG) sites and AD pathology and diagnosis. Here, we report relationships between peripheral blood DNA methylation profiles measured using Infinium® MethylationEPIC BeadChip and AD progression in participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort.

What this study adds

Evidence grade: Moderate

The record lists 19 participants. This study looked at peripheral blood DNA methylation profiles in Alzheimer's Disease Neuroimaging Initiative participants to see if they were related to Alzheimer's disease progression. The rate of cognitive decline was estimated from the initial DNA sampling visit to subsequent visits, and correlations with methylation at specific sites were examined.

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

Li, Q. S., Vasanthakumar, A., Davis, J. W., Idler, K. B., Nho, K., Waring, J. F., et al. (2021). Association of peripheral blood DNA methylation level with Alzheimer's disease progression. Clinical epigenetics. https://doi.org/10.1186/s13148-021-01179-2

Vancouver

Li QS, Vasanthakumar A, Davis JW, Idler KB, Nho K, Waring JF, et al. Association of peripheral blood DNA methylation level with Alzheimer's disease progression. Clinical epigenetics. 2021. doi:10.1186/s13148-021-01179-2. PMID: 34654479.

BibTeX

@article{li2021-34654479,
  author  = {Li, Q. S. and Vasanthakumar, A. and Davis, J. W. and Idler, K. B. and Nho, K. and Waring, J. F. and Saykin, A. J.},
  title   = {{Association of peripheral blood DNA methylation level with Alzheimer's disease progression}},
  journal = {Clinical epigenetics},
  year    = {2021},
  doi     = {10.1186/s13148-021-01179-2},
  pmid    = {34654479},
  url     = {https://doi.org/10.1186/s13148-021-01179-2}
}

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.

How to read this study

Design: our record does not state a study design, so check the methods section of the original before weighing the result.
Size: the record lists 19 participants. Ask whether that is enough for the question, and who they were.
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 moderate. alzhub.org assigns the grade automatically from keywords in the abstract, not from reading the paper. Moderate means the abstract mentions a cohort, case-control or longitudinal design. 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

Epigenome-wide association studies have revealed correlations between DNA methylation at cytosine-phosphate-guanine (CpG) sites and AD pathology and diagnosis.
Here, we report relationships between peripheral blood DNA methylation profiles measured using Infinium® MethylationEPIC BeadChip and AD progression in participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort.
Results The rate of cognitive decline from initial DNA sampling visit to subsequent visits was estimated by the slopes of the modified Preclinical Alzheimer Cognitive Composite (mPACC; mPACC digit and mPACC trailsB ) and Clinical Dementia Rating Scale Sum of Boxes (CDR-SB) plots using robust linear regression in cognitively normal (CN) participants and patients with mild cognitive impairment (MCI), respectively.
In addition, diagnosis conversion status was assessed using a dichotomized endpoint.

Why it matters

This study looked at peripheral blood DNA methylation profiles in Alzheimer's Disease Neuroimaging Initiative participants to see if they were related to Alzheimer's disease progression. The rate of cognitive decline was estimated from the initial DNA sampling visit to subsequent visits, and correlations with methylation at specific sites were examined.

Study details

Participants19
Evidence strengthModerate

How this study scored 51/100

Published in a peer-reviewed journal. Scored zero for study design, effect reported 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 49 of the 96 points we could judge it on, which is 51 out of 100.

Component	Points	Why
Journal tier	7 / 10	Tier 3 — peer-reviewed journal (Clinical epigenetics)
Journal's citation record	1 / 4	Clinical Epigenetics: journal h-index 114 (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	3 / 5	Rated “moderate” in our summary
Peer-review validation	10 / 10	Peer-reviewed. Published as an article in a named peer-reviewed journal.
How recent	3 / 5	2021 — within 6 year(s) of the newest study here
Sample size	1 / 4	19 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)
Randomized / blinded	0 / 2	No randomization or blinding stated — scores zero (not stated in the record — scored 0)
Times cited	4 / 7	Cited 70 times (OpenAlex, 2026-10-10)
Citations per year	3 / 5	10.0 citations a year over 7 year(s) since 2021
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	1 / 6	Cited by 2 other studies in this library
Still being cited	2 / 4	Cited 42 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	1 / 3	Indiana University School of Medicine: institution h-index 784 (OpenAlex)
Multicenter collaboration	2 / 3	OpenAlex lists 5 institution(s) in 1 country
Indexed in PubMed	2 / 2	Indexed in PubMed (PMID 34654479)
Free to read	2 / 2	Free to read
Points	49 / 96	Scored on 19 of 20 parts. We have no data for the rest, so they are left out: 49 of the 96 points we could judge it on is 51 out of 100.
Total	51 / 100	—

What each of these 20 components measures, and what this score is not →

Read the original

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