Evidence map›Paper›PMID 39921333›Full record

ArticleJournal of clinical laboratory analysis2025

Measuring Hemoglobin A1C with Frozen Packed Cell and Frozen Whole Blood Samples in an Epidemiologic Study: The Reasons for Geographic and Racial Differences in Stroke Study.

Debora Kamin Mukaz, Stephanie Tison, D Leann Long, April P Carson, Kelly J Hunt, Suzanne E Judd, Mary Cushman

Abstract read
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In one paragraph

Article in Journal of clinical laboratory analysis, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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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

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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

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5 · Who and what money

Authors and funding

7 authors.

Debora Kamin MukazDepartment of Medicine, Larner College of Medicine, University of Vermont, Burlington, Vermont, USA.ORCID https://orcid.org/0000-0001-5573-2573
Stephanie TisonOffice of Data Science and Sharing, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland, USA.
D Leann LongDepartment of Biostatistics and Data Science, School of Medicine, Wake Forest University, Winston-Salem, North Carolina, USA.
April P CarsonDepartment of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA.
Kelly J HuntDepartment of Public Health Sciences, Medical University of South Carolina, Charleston, South Carolina, USA.
Suzanne E JuddDepartment of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama, USA.
Mary CushmanDepartment of Medicine, Larner College of Medicine, University of Vermont, Burlington, Vermont, USA.

Funding

VCID and Stroke in a Bi-racial National CohortU01NS041588 · NINDS · UNIVERSITY OF ALABAMA AT BIRMINGHAM · PI CUSHMAN, MARY, HOWARD, GEORGE · 2002 to 2022
$96.0M
Vermont Center for Cardiovascular and Brain HealthP20GM135007 · NIGMS · UNIVERSITY OF VERMONT & ST AGRIC COLLEGE · PI Diego Adrianzen Herrera · 2020 to 2026
$17.4M
Exposome Contributors to Child Health Originating from National Fetal Growth Study (ECCHO-NFGS)UG3OD023316 · OD · MEDICAL UNIVERSITY OF SOUTH CAROLINA · PI HUNT, KELLY J, WAPNER, RONALD · 2016 to 2017
$10.8M
NIA NIH HHS U01 NS041588NIGMS NIH HHS P20 GM135007NIGMS NIH HHS P20GM135007NIH HHS UG3 OD023316NIH Office of the Director UG3OD023316NINDS NIH HHS U01 NS041588NINDS NIH HHS U01NS041588
6 · The paper itself

Abstract

introductionHemoglobin A1c (HbA1c) measurement in epidemiology studies could be increased if reliability of measurements in frozen stored samples was known. In the Reasons for Geographic And Racial Differences in Stroke, a longitudinal study of 30,239 Black and White U.S. adults, we investigated reliability of HbA1c measurements for two types of samples stored at -80°C for up to 14 years.

methodsAmong 917 participants without diabetes, HbA1c was measured in 2017 in frozen packed cells from the first visit (2003-2007) and in frozen whole blood samples from the second visit (2013-2016). To study reliability, associations between HbA1c and glycemia-related characteristics were examined.

resultsEach 10 mg/dL greater fasting glucose was associated with 0.08% (95% CI: 0.05%-0.11%) greater HbA1c in frozen packed cells (Visit 1) and 0.10% (95% CI: 0.08%-0.12%) greater HbA1c in whole blood (Visit 2). HbA1c was also similarly higher with both methods with increasing age, gender, systolic blood pressure, body mass index, high-density lipoprotein, triglycerides, C-reactive protein, and hemoglobin. Using both methods, ≤ 3.5% would be classified with diabetes based on HbA1c ≥ 6.5%.

conclusionsIn REGARDS participants without diabetes, HbA1c measurement appeared reliable in frozen packed cells or whole blood under long-term storage, suggesting acceptability for study of the epidemiology of HbA1c.

Indexed as

Glycated HemoglobinStrokeAdultAgedBlack or African AmericanBlood GlucoseCryopreservationFemaleFreezingHumansLongitudinal StudiesMaleMiddle AgedReproducibility of ResultsUnited StatesWhiteBlood GlucoseGlycated Hemoglobinhemoglobin A1c protein, humanA1cblood preservationfrozen samplesglycated hemoglobinpacked cells

Identifiers

PMID39921333
PMCPMC11848213

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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 OpenQuestion graph.