Evidence map›Paper›PMID 42396324›Full record

ArticlemedRxiv : the preprint server for health sciences2026

Reliable quantification of renal function from frozen blood samples.

Scott R French, Gavin C Culwell, Haley E Wiskoski, Juan C Arias, Summan Zahra, Cris E Escareno, Emma N Heitkamp, Anozira R Garcia, Paola Vidana, Josue B Quijada and 6 more

Abstract readPreprint
In one paragraph

Article in medRxiv : the preprint server for health sciences, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

16 authors.

Scott R FrenchThe Division of Vascular Surgery, University of Arizona, 1501 N. Campbell Ave., Tucson, Arizona 85724, USA.ORCID 0009-0004-1747-949X
Gavin C CulwellThe Division of Vascular Surgery, University of Arizona, 1501 N. Campbell Ave., Tucson, Arizona 85724, USA.
Haley E WiskoskiThe Division of Vascular Surgery, University of Arizona, 1501 N. Campbell Ave., Tucson, Arizona 85724, USA.ORCID 0009-0004-2271-0406
Juan C AriasThe Division of Vascular Surgery, University of Arizona, 1501 N. Campbell Ave., Tucson, Arizona 85724, USA.ORCID 0000-0002-3365-2377
Summan ZahraThe Division of Vascular Surgery, University of Arizona, 1501 N. Campbell Ave., Tucson, Arizona 85724, USA.ORCID 0000-0002-9185-3361
Cris E EscarenoThe Division of Vascular Surgery, University of Arizona, 1501 N. Campbell Ave., Tucson, Arizona 85724, USA.
Emma N HeitkampThe Division of Vascular Surgery, University of Arizona, 1501 N. Campbell Ave., Tucson, Arizona 85724, USA.
Anozira R GarciaThe Division of Vascular Surgery, University of Arizona, 1501 N. Campbell Ave., Tucson, Arizona 85724, USA.
Paola VidanaThe Division of Vascular Surgery, University of Arizona, 1501 N. Campbell Ave., Tucson, Arizona 85724, USA.
Josue B QuijadaThe Division of Vascular Surgery, University of Arizona, 1501 N. Campbell Ave., Tucson, Arizona 85724, USA.
Raffael KasparovThe Division of Vascular Surgery, University of Arizona, 1501 N. Campbell Ave., Tucson, Arizona 85724, USA.
Francesca VitaliDepartment of Neurology, University of Arizona, 1501 N. Campbell Ave., Tucson, Arizona 85724, USA.ORCID 0000-0003-2916-6402
Edward J BedrickDepartment of Epidemiology and Biostatistics, University of Arizona, 1230 N. Cherry Ave., Tucson, Arizona 85721, USA.ORCID 0000-0002-4215-795X
Raza MushtaqDepartment of Neuroradiology, Barrow Neurological Institute, 2910 N. 3rd Ave., Phoenix, Arizona 85013, USA.
Gene E AlexanderArizona Alzheimer's Consortium, 4745 N. 7th St., Ste. 105, Phoenix, Arizona 85014, USA.ORCID 0000-0002-6476-5606
Craig C WeinkaufThe Division of Vascular Surgery, University of Arizona, 1501 N. Campbell Ave., Tucson, Arizona 85724, USA.ORCID 0000-0001-9696-5613

Funding

Research Education ComponentP30AG072980 · NIA · BANNER HEALTH · PI ALIREZA ATRI · 2021 to 2026
$24.9M
Improvement of Overall recruitment, Latino Community Outreach and MRI acquisitionR01AG070987 · NIA · UNIVERSITY OF ARIZONA · PI WEINKAUF, CRAIG C · 2021 to 2025
$6.5M
NIA NIH HHS P30 AG072980NIA NIH HHS R01 AG070987
6 · The paper itself

Abstract

backgroundDifferences in renal function may affect Alzheimer's disease (AD) blood biomarker levels independent of AD pathology. Although renal function was unaccounted for in foundational AD blood biomarker studies, there is potential to address this through quantification of estimated glomerular filtration rate (eGFR) from frozen serum and plasma samples. However, the validity of eGFR evaluation from long-term frozen blood samples is unknown.

methodsAdults aged 50-85 with ≥2 vascular risk factors were recruited from vascular surgery or cardiology clinics in Tucson, Arizona from 2022-2025. Individuals with creatinine assessments in point-of-care whole blood (POC-WB) and frozen serum and plasma samples using the iSTAT (Abbott) were included. eGFR was calculated using the 2021 CKD-EPI creatinine equation without race. Agreement between POC-WB and frozen blood samples was assessed using Cohen's kappa with linear weights.

results134 participants (mean age: 72.6 ± 7.5 years, 39.6% female, 23.1% chronic kidney disease) had POC-WB eGFR available. Frozen serum and plasma samples had strong agreement with POC-WB for eGFR (Kw= 0.90-0.95, P<0.001). Pre-analytical factors had minimal effect on eGFR differences between POC-WB and frozen blood samples.

conclusionsRenal function can be assessed from frozen blood samples with high consistency to POC-WB, which may be particularly relevant for interpretation of AD blood biomarkers in general aging and vascular populations who often have impaired renal function.

Indexed as

ADRDAlzheimer's diseasebiomarkersChronic Kidney diseaseCreatinineeGFRPlasmapoint-of-care testingpTau217Renal FunctionSerum

Identifiers

PMID42396324
PMCPMC13321177

What Socratic holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.