Should adult criteria for prediabetes be applied to youngsters?

A study of hemoglobin A1c (HbA1c) levels that compared levels in normal-weight and obese middle schoolers found that overall distribution of HbA1c was similar in the 2 groups and that the adult-defined cutoff was seen in 2% of normal-weight youth. Based on previously published epidemiologic data, the authors concluded that in youngsters these adult prediabetes levels are highly unlikely to represent evolving diabetes and recommended that results of HbA1c screening in children “be interpreted with caution.”

The trial looked at 8814 normal-weight and obese youngsters (4603 and 4211 in each group, respectively) aged from 11 years to 15 years. For most participants, HbA1c assessments were conducted in either sixth or eighth grade and at both times for some. Although mean HbA1c was higher in obese youth compared with those of normal weight, overall HbA1c was similar in the 2 groups, with 2 of every 100 normal-weight youngsters having a level in the prediabetes range. However, normal-weight black children had significantly higher HbA1c levels than other participants, with 7.1% in the prediabetes range compared with 1.3% of Hispanic children and 0.1% of white children (Kelsey MM, et al. J Pediatr. 2020;216:232-235).

Thoughts from Dr. Farber

The incidence of type 2 diabetes in children continues to rise. Hemoglobin A1c is often used to screen for prediabetes but has not been confirmed to be reliable in children. This study suggests caution in its use. I would go further and recommend not using it in normal-weight children, even with a positive family history.