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7 FDA Approved CSF Biomarkers Demonstrate Strong Predictive Value for Identification of Alzheimer Disease Based on PET Scan in Patients with Standalone Alzheimer Cognitive Screening Tests
Corey Crecelius, Melody Nelson, Andrew Jones, Candice R. Coffey. American Journal of Clinical Pathology, 2025-11-01
Topic: Amyloid, tau and blood-test diagnosis
Results There was no statistically significant difference in age of patients with the CSF biomarker ratio above the cut off limit of 0.024 (80 patients, mean age 71.3 years, SD: 7.9) and ratio below the cut-off (63 patients, mean age 66.3 years, SD :10.0) using Levene’s test. We observed no racial bias (Caucasian, African American, Hispanic and others) in elevated CSF biomarker results or positive PET scans using Chi-Square test. Chi-square analysis also showed a statistically significant association between positive CSF tests and PET scans (p < 0.01). The mean pTau181/Ab42 ratio was 0.055 (SD: 0.05, range: 0.025-0.12) in patients resulted positive for the CSF biomarkers, but the ratio was 0.0138 (SD: 0.0046, range: 0.007-0.024) in patients who tested negative (differences were also statistically significant by t-test). The sensitivity of pTau181/Ab42 was 76.2%, specificity was 84.2% and positive predictive value was 84.2% when compared to PET scan findings. We observed poor correlation between standalone SCF and PET scan result using Chi-Square analysis. However, binary logistic regression demonstrated a combination of abnormal SCF, and a positive CSF screen significantly predicted a positive imaging result (N = 40, p<.001). Conclusions CSF pTau181/Ab42 ratio is a diagnostic marker for Alzheimer disease correlated well with PET scan compared to various standalone cognitive screening assessment. A negative CSF biomarker test result may help rule out Alzheimer disease. Further, a combination approach inclusive of SCF and CSF biomarkers was significant for positive PET imaging.
Key findings
- Results There was no statistically significant difference in age of patients with the CSF biomarker ratio above the cut off limit of 0.024 (80 patients, mean age 71.3 years, SD: 7.9) and ratio below the cut-off (63 patients, mean age 66.3 years, SD :10.0) using Levene’s test.
- We observed no racial bias (Caucasian, African American, Hispanic and others) in elevated CSF biomarker results or positive PET scans using Chi-Square test.
- Chi-square analysis also showed a statistically significant association between positive CSF tests and PET scans (p < 0.01).
- The mean pTau181/Ab42 ratio was 0.055 (SD: 0.05, range: 0.025-0.12) in patients resulted positive for the CSF biomarkers, but the ratio was 0.0138 (SD: 0.0046, range: 0.007-0.024) in patients who tested negative (differences were also statistically significant by t-test).
- The sensitivity of pTau181/Ab42 was 76.2%, specificity was 84.2% and positive predictive value was 84.2% when compared to PET scan findings.
Why it matters
This study found that the CSF pTau181/Ab42 ratio correlated well with PET scan findings and had a sensitivity of 76.2% and specificity of 84.2% for identifying Alzheimer's disease. It is about diagnosis, not treatment, and does not demonstrate any cure or prevention.
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Study details
- Participants40
- Effect size76.2%; 84.2%; 50.0%
- Evidence strengthLow
How this study scored 34/100
Published in a peer-reviewed journal. Scored zero for study design and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (American Journal of Clinical Pathology) |
| Journal's citation record | 2 / 4 | American Journal of Clinical Pathology: journal h-index 223 (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 | 4 / 5 | 2025 — within 3 year(s) of the newest study here |
| Sample size | 1 / 4 | 40 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 | 0 / 7 | Cited 0 times (OpenAlex, 2026-10-10) |
| Citations per year | 0 / 5 | 0.0 citations a year over 3 year(s) since 2025 |
| Impact for its field and year | 0 / 6 | Cited 0.0× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 0 / 4 | Cited 0 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 0 / 4 | Last-listed author Candice R. Coffey: h-index 2 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | University of Kansas: institution h-index 709 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 1 / 2 | Not in PubMed, but has a DOI |
| Free to read | 2 / 2 | Free to read |
| Total | 34 / 100 | — |
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Read the original
- DOI: 10.1093/ajcp/aqaf121.434
- Original source →
- Free full text: American Journal of Clinical Pathology →
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. Check the citation against the original before you use it.
APA 7th
Crecelius, C., Nelson, M., Jones, A., & Coffey, C. R. (2025). 7 FDA Approved CSF Biomarkers Demonstrate Strong Predictive Value for Identification of Alzheimer Disease Based on PET Scan in Patients with Standalone Alzheimer Cognitive Screening Tests. American Journal of Clinical Pathology. https://doi.org/10.1093/ajcp/aqaf121.434
Vancouver
Crecelius C, Nelson M, Jones A, Coffey CR. 7 FDA Approved CSF Biomarkers Demonstrate Strong Predictive Value for Identification of Alzheimer Disease Based on PET Scan in Patients with Standalone Alzheimer Cognitive Screening Tests. American Journal of Clinical Pathology. 2025. doi:10.1093/ajcp/aqaf121.434.
BibTeX
@article{crecelius2025-dd3a1324,
author = {Crecelius, Corey and Nelson, Melody and Jones, Andrew and Coffey, Candice R.},
title = {{7 FDA Approved CSF Biomarkers Demonstrate Strong Predictive Value for Identification of Alzheimer Disease Based on PET Scan in Patients with Standalone Alzheimer Cognitive Screening Tests}},
journal = {American Journal of Clinical Pathology},
year = {2025},
doi = {10.1093/ajcp/aqaf121.434},
url = {https://doi.org/10.1093/ajcp/aqaf121.434}
}
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