From the Research
Hemoglobin A1c testing is not recommended for children less than 6 months old. In infants under 6 months, hemoglobin A1c values are unreliable because newborns have predominantly fetal hemoglobin (HbF) at birth, which gradually transitions to adult hemoglobin (HbA) over the first 4-6 months of life 1. This transition period affects the accuracy of A1c measurements, potentially leading to falsely low or misleading results. Additionally, the red blood cells in newborns have a shorter lifespan compared to adults, further complicating the interpretation of A1c values which reflect average blood glucose over the lifespan of red blood cells.
Some studies have explored alternative methods for monitoring glucose levels, such as labile glycated hemoglobin (l-HbA1c) 2, and point-of-care testing using invasive and non-invasive hemoglobinometers 3. However, these methods are not directly relevant to the use of hemoglobin A1c in infants under 6 months. Other studies have discussed the limitations of HbA1c testing, including racial and ethnic differences in the relationship between HbA1c and blood glucose 4, and the increase in HbA1c levels during red blood cell storage 5.
For diagnosing or monitoring diabetes in infants under 6 months, alternative methods such as plasma glucose measurements, fasting glucose tests, or glucose tolerance tests are more appropriate and reliable. If diabetes is suspected in a very young infant, consultation with a pediatric endocrinologist is recommended for proper evaluation and management. The most recent and highest quality study on this topic is from 2021, which highlights the importance of using alternative methods for diagnosing and monitoring diabetes in infants under 6 months 1.
Key points to consider:
- Hemoglobin A1c values are unreliable in infants under 6 months due to the transition from fetal to adult hemoglobin
- Red blood cells in newborns have a shorter lifespan, complicating the interpretation of A1c values
- Alternative methods, such as plasma glucose measurements and glucose tolerance tests, are more appropriate for diagnosing and monitoring diabetes in infants under 6 months
- Consultation with a pediatric endocrinologist is recommended for proper evaluation and management of suspected diabetes in very young infants.