Continuous Glucose Monitoring and its Relationship to Hemoglobin A1c and Oral Glucose Tolerance Testing in Obese and Prediabetic Youth

Context: The optimal screening test for diabetes and prediabetes in obese youth is controversial. Objective: We examined whether glycosylated hemoglobin (HbA1c) or the oral glucose tolerance test (OGTT) is a better predictor of free-living glycemia as measured by continuous glucose monitoring (CGM). Design: This was a cross-sectional study of youth 10–18 years old, body mass index (BMI) 85th percentile or greater, with diabetes risk factors. Setting and Participants: Participants (n = 118) with BMI 85th percentile or greater, not on medications for glucose management, were recruited from primary care and pediatric endocrinology clinics around Denver, Colorado. Intervention: HbA1c, fasting plasma glucose, and 2-hour glucose were collected and all participants wore a blinded CGM for 72 hours. Main Outcome Measures: CGM outcomes were determined and descriptive statistics calculated. Performance characteristics at current American Diabetes Association cutpoints were compared with CGM outcomes. Results: CGM da...