Reversal of Early Abnormalities in Glucose Metabolism in Obese Youth: Results of an Intensive Lifestyle Randomized Controlled Trial

Abstract

OBJECTIVE The childhood obesity epidemic has been accompanied by an increasing prevalence of type 2 diabetes (T2D), particularly in minority children. Twenty to thirty percent of obese youth have “prediabetes,” a precursor to diabetes marked by insulin resistance, β-cell dysfunction, and impaired glucose tolerance. The Diabetes Prevention Program demonstrated that T2D could be prevented/delayed by intensive lifestyle modification in adults with prediabetes, but efficacy of similar interventions in youth has not been established. Therefore, we evaluated the effects of the Bright Bodies (BB) Healthy Lifestyle Program on 2-h oral glucose tolerance test (OGTT) glucose in comparison with adolescents receiving standard of care. RESEARCH DESIGN AND METHODS A parallel-group randomized controlled trial comparing BB with standard clinical care (CC) in obese adolescents (10–16 years old, Tanner stage >2) with elevated OGTT 2-h blood glucose (130–199 mg/dL) from a racially/ethnically diverse population. OGTTs, including cardiovascular and anthropometric assessments, were conducted at baseline and 6 months. Children attended BB twice per week for exercise and nutrition/behavior modification, and the CC group received CC from their pediatrician. Primary outcome was change in 2-h OGTT glucose and percentage conversion from elevated 2-h blood glucose to nonelevated (<130 mg/dL) 2-h blood glucose. Changes in outcomes were compared between groups using an ANCOVA, with adjustment for baseline outcome and multiple imputation for missing data. RESULTS Reductions in 2-h glucose were more favorable in BB compared with CC (−27.2 vs. −10.1 mg/dL; difference = −17.1, 95% CI; P = 0.005). Moreover, greater conversion to <130 mg/dL 2-h glucose occurred in BB than CC (P = 0.003), and other insulin sensitivity indices were significantly improved. CONCLUSIONS Compared with standard of care, the Yale BB Program is a more effective means of reducing the risk of T2D in obese adolescents with elevated 2-h glucose levels.