Screening for Dysglycemia in Overweight Youth Presenting for Weight Management

OBJECTIVE: To examine the performance of current screening recommendations for detecting dysglycemia in children and adolescents with obesity. RESEARCH DESIGN AND METHODS: In a cross-sectional study, an oral glucose tolerance test and demographic (age, sex, family history of diabetes, and ethnicity), clinical (BMI z score, waist circumference, and pubertal stage), and laboratory variables used in current pediatric screening criteria for type 2 diabetes mellitus were measured in 259 overweight or obese youth aged 5-17 years. Glycemic status was based on American Diabetes Association (ADA) thresholds. The performance (sensitivity and specificity) of current screening criteria and newly developed models to identify isolated IGT were compared. RESULTS: Dysglycemia was present in 20.8% of the cohort. Of the 54 participants with dysglycemia, 68% had a normal fasting glucose and were identified with the 2-h glucose test. Current ADA criteria had low sensitivity (41.7% [95% CI 25.6-57.8]) and moderate specificity (69.5% [63.5-75.6]) to identify IGT. In receiver operating characteristic (ROC) analysis, the addition of hemoglobin A(1c) (HbA(1c)) or FPG did not improve the ROC area under the curve (AUC) (HbA(1c): 0.64 vs. 0.63; P = 0.54; HbA(1c) + FPG: 0.66; P = 0.42), but adding triglyceride level did (AUC 0.72 vs. 0.63; P = 0.03). A simple model with fasting triglyceride level >1.17 mmol/L improved AUC compared with ADA screening criteria (0.68 vs. 0.57; P = 0.04). CONCLUSIONS: The prevalence of IGT is high among obese children and youth. Current screening criteria have low sensitivity to detect isolated IGT. Although adding nonfasting laboratory values to history and physical measures does not improve diagnostic accuracy, adding fasting lipid profile improves predictive value.