Due to a high percentage of hemoglobin F, Hemoglobin A1C (HbA1C) measurements are inaccurate for assessing glycemia in infants. We aimed to determine when HbA1C might have utility and to assess the value of fructosamine. We measured HbA1C in healthy infants aged 3 weeks to 12 months. Hemoglobin, HbA1C, hemoglobin electrophoresis, fructosamine, and albumin levels were collected. Mean age was 193.9 ± 94.5 days; participants were 60.9% male, 80.4% white, and 15.2% Hispanic. Mean HbA1C (n=31) and fructosamine (n=33) were 5.0% (31 mmol/mol) (range 4.4–5.9%; 25–41 mmol/mol) and 217 (range 186–261 mCmol/L), respectively. HbA1C percentages negatively correlated with HbF percentages (p < 0.005) and rose with increasing age in infants <6 months (p < 0.01). Fructosamine did not vary with age. Normalizing HbA1C to hemoglobin fractions or fructosamine to albumin did not change significance. We conclude that HbA1C values (via HPLC) likely become a reliable marker of glycemia after 6 months of age and that fructosamine may be a better measure during this young age.

The authors have declared no competing interest.

This project was funded by a Pediatric Fellows Grant from the Indiana University School of Medicine, Department of Pediatrics. RSA was also supported by a Ruth L. Kirshchstein Institutional National Research Service Award (grant number 5T32-DK-065549-15).

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The Institutional Review Board at Indiana University, Indiana University (IU) School of Medicine, Indianapolis, IN gave ethical approval for this work.

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I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

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↵* RSA is currently at Baylor College of Medicine.

↵# AA-R is currently at Michigan State University, Lansing. The collection and analysis of the current data occurred at Indiana University.

Author Email addresses: Abeer Al-Raddadi: abalraddgmail.com, Linda A. DiMeglio: dimeglioiu.edu, Erica A. Eugster: eeugsteriu.edu

Grant/Fellowship support: This project was funded by a Pediatric Fellows Grant from the Indiana University School of Medicine, Department of Pediatrics. RSA was also supported by a Ruth L. Kirshchstein Institutional National Research Service Award (grant number 5T32-DK-065549-15).

The authors declare that there are no conflicts of interest regarding publication of this article. Portions of this work were presented as a presidential poster at the 2021 Pediatric Endocrine Society Annual meeting.

Some or all datasets generated during and/or analyzed during the current study are not publicly available but are available from the corresponding author on reasonable request.