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Blood Biomarkers to Detect Alzheimer Disease in Primary Care and Secondary Care
Pontus Tideman, Niklas Mattsson-Carlgren, Suzanne E. Schindler, Ruben Smith, Rik Ossenkoppele, Susanna Calling, Tim West, Mark Monane, Philip B. Verghese, Joel B. Braunstein, Kaj Blennow, Shorena Janelidze, Erik Stomrud, Gemma Salvadó, Oskar Hansson, Sebastian Palmqvist. JAMA, 2024-10-15
Topic: Amyloid, tau and blood-test diagnosis
This Swedish study of over 1,200 people with memory symptoms found that a blood test combining p-tau217 with an amyloid ratio (the 'Amyloid Probability Score 2') was far more accurate at identifying Alzheimer's disease than doctors' clinical judgment alone. The blood test reached about 91% accuracy compared with 73% accuracy for dementia specialists and 61% for primary care doctors using standard exams.
Key findings
- 1,213 patients with cognitive symptoms evaluated in Sweden, 2020-2024
- APS2 blood test AUC of 0.96-0.97, positive predictive value 88-91%
- Blood test accuracy (91%) exceeded that of primary care physicians (61%) and dementia specialists (73%)
Why it matters
A blood test combining p-tau217 and an amyloid ratio identified Alzheimer's disease with 91% accuracy in symptomatic patients, compared with 73% for dementia specialists and 61% for primary care doctors. The study demonstrates improved diagnostic accuracy but does not establish whether this more reliable detection leads to better treatment outcomes.
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Study details
- Study designcross-sectional
- Participants1,213
- Effect sizeAUC 0.96-0.97; accuracy 91% (APS2) vs 61% (primary care physicians) vs 73% (dementia specialists)
- Evidence strengthHigh
Limitations
Single-country (Sweden) memory-clinic/primary-care sample; accuracy benchmarked against clinical judgment rather than an independent external validation cohort.
How this study scored 68/100
Published in a top-tier journal, and it is a snapshot of people at one point in time. Scored zero for randomised / blinded and indexed in PubMed because the record does not state it. We have no data on journal's citation record, times cited, citations per year, impact for its field and year, still being cited, senior author's track record, institution's track record, multi-centre collaboration and free to read, so those were left out: it earned 42 of the 62 points we could judge it on, which is 68 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 10 / 10 | Tier 1 — top-tier general journal (JAMA) |
| Journal's citation record | — / 4 | No journal record from OpenAlex — left out of this score |
| Study design | 4 / 12 | A snapshot of people at one point in time |
| Strength of evidence | 5 / 5 | Rated “high” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 4 / 5 | 2024 — within 3 year(s) of the newest study here |
| Sample size | 3 / 4 | 1,213 participants |
| Effect reported | 3 / 3 | Effect reported with a statistic (interval, p-value, ratio or similar) |
| 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 | — / 7 | No citation count (not found in OpenAlex) — left out of this score |
| Citations per year | — / 5 | No citation count or no year — left out of this score |
| Impact for its field and year | — / 6 | No field-weighted citation impact (OpenAlex has none yet) — left out of this score |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | — / 4 | No yearly citation counts — left out of this score |
| Senior author's track record | — / 4 | Senior author's record not available — left out of this score |
| Institution's track record | — / 3 | No institution listed in OpenAlex — left out of this score |
| Multi-centre collaboration | — / 3 | Institutions not listed — left out of this score |
| Indexed in PubMed | 0 / 2 | No PubMed ID and no DOI — scores zero (not stated in the record — scored 0) |
| Free to read | — / 2 | Access not recorded — left out of this score |
| Points | 42 / 62 | Scored on 11 of 20 parts. We have no data for the rest, so they are left out: 42 of the 62 points we could judge it on is 68 out of 100. |
| Total | 68 / 100 | — |
What each of these 20 components measures, and what this score is not →
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. This record has no DOI, so the citation leaves it out. Volume, issue and page numbers are not held in the record. The record names 16 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
Tideman, P., Mattsson-Carlgren, N., Schindler, S. E., Smith, R., Ossenkoppele, R., Calling, S., et al. (2024). Blood Biomarkers to Detect Alzheimer Disease in Primary Care and Secondary Care. JAMA.
Vancouver
Tideman P, Mattsson-Carlgren N, Schindler SE, Smith R, Ossenkoppele R, Calling S, et al. Blood Biomarkers to Detect Alzheimer Disease in Primary Care and Secondary Care. JAMA. 2024. PMID: 39068545.
BibTeX
@article{tideman2024-e791e2c1,
author = {Tideman, Pontus and Mattsson-Carlgren, Niklas and Schindler, Suzanne E. and Smith, Ruben and Ossenkoppele, Rik and Calling, Susanna and West, Tim and Monane, Mark and Verghese, Philip B. and Braunstein, Joel B. and Blennow, Kaj and Janelidze, Shorena and Stomrud, Erik and Salvadó, Gemma and Hansson, Oskar and Palmqvist, Sebastian},
title = {{Blood Biomarkers to Detect Alzheimer Disease in Primary Care and Secondary Care}},
journal = {JAMA},
year = {2024},
pmid = {39068545}
}
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