Evaluation of the hemoglobin a1c test in detecting pediatric prediabetes

Aim: It was aimed to evaluate the diagnostic performance of the hemoglobin A1c (HbA1c) test in pediatric prediabetes, and to determine the cut-off value for the adolescent. Material and Method: This study was carried out by retrospectively evaluating the data of 379 adolescents aged between 10 and 18 years. Prediabetes was diagnosed based on glucose criteria, either the fasting glucose value or the 2-hour (2h) glucose value during a 75 g oral glucose tolerance test (OGTT), or HbA1c criteria. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for fasting, OGTT 2h glucose, and HbA1c. The area under the curve (AUC) was calculated for each test by receiver-operating characteristic analysis. Results: 2.1% of individuals were assigned to the diabetes mellitus group, 21.9% to the prediabetes group, and 76.0% to the normoglycemia group. When 5.7 was used as the threshold value for HbA1c in prediabetes, the sensitivity was 53.0%. The AUC was 0.83 for the HbA1c test. An HbA1c threshold of 5.55% was determined as the optimal cut-off for diagnosing prediabetes, with 62.7% sensitivity and 93.0% specificity. Conclusion: Although the use of adults’ HbA1c criteria for the diagnosis of prediabetes in the pediatric ages is controversial due to the differences between the results of glucose and HbA1c-based tests, prediabetes screening is still important. HbA1c≥5.55 will be useful to follow up on adolescents with prediabetes in terms of risk and to screen them with blood glucose.