title: Development of filter paper hemoglobin A1c assay applicable to newborn screening.
abstract: OBJECTIVE
  Gestational diabetes influences risk for future metabolic disease including type 2 diabetes. Hemoglobin A1c (HbA1c) measurement assesses hemoglobin A glycosylation, and could theoretically be used as a test to estimate gestational glucose exposure. HbA1c assay on dried blood spots (DBS) is needed before potential application to statewide newborn screening (NBS) population studies. The study aimed to establish a reliable method to measure HbA1c on NBS DBS specimens. De-identified blood was used to generate trials to evaluate stability of HbA1c in DBS, optimal elution time, and stability of eluted blood.
  
  
  RESULTS
  Analysis of DBS stability HbA1c measurements from 3 to 6days after collection overestimated HbA1c values by a bias factor between 0.83 and 0.87. Sixty minutes of elution time produced maximal reproducibility and minimal bias of results. Within assay standard deviation: 0.058; average bias: -0.02%. Stability of eluted blood did not vary significantly between days 0-2 after DBS elution.
  
  
  CONCLUSIONS
  Measurement of HbA1c levels on DBS from human blood is feasible. Results suggest new method using DBS to measure HbA1c level with the following characteristics: optimal time for sample analysis 3-6days after collection, elution time of 60min and eluted blood analysis within 2days of elution. Measurement of neonatal HbA1c could provide insight regarding the infant's in utero exposure to glucose.
authors.affiliation: University of Wisconsin School of Medicine and Public Health, 600 Highland Avenue, Madison, WI 53792, USA. Electronic address: apollock@pediatrics.wisc.edu.
authors.forename: Allison J
authors.initials: AJ
authors.lastname: Pollock
authors.affiliation: University of Wisconsin School of Medicine and Public Health, 600 Highland Avenue, Madison, WI 53792, USA.
authors.forename: David B
authors.initials: DB
authors.lastname: Allen
authors.affiliation: University of Wisconsin School of Medicine and Public Health, 600 Highland Avenue, Madison, WI 53792, USA.
authors.forename: Donald
authors.initials: D
authors.lastname: Wiebe
authors.affiliation: University of Wisconsin School of Medicine and Public Health, 600 Highland Avenue, Madison, WI 53792, USA.
authors.forename: Jens
authors.initials: J
authors.lastname: Eickhoff
authors.affiliation: University of Wisconsin School of Medicine and Public Health, 600 Highland Avenue, Madison, WI 53792, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: MacDonald
authors.affiliation: University of Wisconsin School of Medicine and Public Health, 600 Highland Avenue, Madison, WI 53792, USA; Wisconsin State Laboratory of Hygiene, 2601 Agriculture Dr, Madison, WI 53718, USA.
authors.forename: Mei
authors.initials: M
authors.lastname: Baker
mesh_terms: D059788:Dried Blood Spot Testing; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D007231:Infant, Newborn; D015997:Neonatal Screening / Q000379:methods*; D015203:Reproducibility of Results
chemical_list: D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human
keywords: Diabetes; Filter paper; Hemoglobin A1c; Newborn screening; Obesity