Oral glucose tolerance and HbA1C tests can better diagnose children with diabetes.
Findings from a new study suggest that additional tests may be needed to adequately screen high-risk children for pre-diabetes and diabetes.
The study, which was presented at the annual scientific meeting of the Endocrine Society, suggests that high-risk children should also receive an oral glucose tolerance test (OGTT), in addition to standard hemoglobin A1C (HbA1C) testing for a more accurate diagnosis.
"We recommend the combined use of fasting and 2-hour glucose levels, in addition to HbA1C, for the diagnosis of childhood prediabetes and diabetes," said study first author Hyo-Kyoung Nam, MD, PhD. "Traditionally, plasma glucose levels obtained from oral glucose tolerance tests have been used to diagnose prediabetes and diabetes. Hemoglobin A1C, which is easy to use and does not require fasting, has recently been recommended as an alternative diagnostic method in adults. However, using HbA1C to diagnose prediabetes and diabetes in children and adolescents is controversial.”
In the study, the authors examined the efficacy of using HbA1C to diagnose prediabetes and diabetes in children. They also created optimal HbA1C measures for detecting the condition in this population.
Included in the study were 217 boys and 172 girls with obesity who were administered OGTT and HbA1C testing between January 2010 and June 2016. These children were diagnosed with prediabetes — fasting glucose 5.6 to 6.9 mmol/L; 2-hour glucose 7.8 to 11.0 mmol/L) or diabetes (fasting glucose 7.0 mmol/L or higher; 2-hour glucose 11.1 mmol/L or higher).
The authors reported that all children with diabetes were diagnosed through the use of both tests. Approximately 50% of high-risk children with either condition were diagnosed based on OGTT results. There was moderate agreement between OGTT and HbA1C tests, according to the study.
The authors noted that the optimal HbA1C cutoff points were 40 mmol/mol (5.8%) for prediabetes and 44 mmol/mol (6.2%) for diabetes in children.
Currently, the cutoffs used for adults may not be accurate among younger individuals due to differing factors.
"The usefulness of adult criteria of HbA1C for the diagnosis of prediabetes and diabetes in children and adolescents remains to be clarified due to disparities between the results of OGTT- and HbA1C-based tests," Dr Nam said.
With the guidance of the new study, children may be able to receive a more accurate preliminary risk assessment and diagnosis.
Since the prevalence of diabetes among children continues to increase, having a more focused testing method that includes both OGTT and HbA1C could improve diagnoses and, subsequently, patient outcomes, according to the study.
"The trend in the prevalence of type 2 diabetes mellitus in the pediatric population is rising,” Dr Nam concluded. “Early detection of prediabetes and early diabetes is crucial to enable preventive management of cardiovascular disease. Diabetes-related complications and mortality can lead to major financial burden in individuals with diabetes.”