Effects of a Comprehensive, Intensive Lifestyle Intervention Combined with Metformin Extended Release in Obese Adolescents.

Objective. To assess a comprehensive, intensive lifestyle intervention in combination with metformin extended release (MXR) or placebo on body mass index (BMI) and risk factors for type 2 diabetes and cardiovascular disease in obese adolescents. Study Design. Sixty-nineobese adolescents (mean BMI 32.5) received a comprehensive lifestyle intervention with structured dietary, physical activity, and behavioral components for 24 months. Subjects were randomized to 1 of 4 groups: MXR (33) 2,000 mg daily or placebo, with either moderate or vigorous intensity exercise for the first 3 months. Subsequently the exercise intervention was the same for all 4 groups. Results. Anthropometry measurements did not differ with initial exercise intensity at any time. At 3 months % body fat decreased in all 4 groups (P < 0.006). BMI and % body fat decreased in the MXR groups, but not the placebo groups, at 6 (-0.88, -3.16) and 12 months (-0.56, -2.34) (P < 0.05). Insulin resistance, fasting blood glucose, and leptin improved in all groups at 6 and 12 months. A high subject attrition rate (58%) occurred by 24 months. Conclusion. A comprehensive, intensive lifestyle intervention combined with MXR led to a decline in BMI and % body fat at 1 year independent of initial exercise intensity. This trial is registered with ClinicalTrials.gov NCT00934570 .