Effects of exenatide versus insulin glargine on body composition in overweight and obese T2DM patients: a randomized controlled trial

BACKGROUND: Weight loss, especially fat mass reduction, helps to improve blood glucose control, insulin sensitivity, and β-cell function. This study aimed to compare the effect of exenatide and glargine on body composition in overweight and obese patients with type 2 diabetes (T2DM) who do not achieve adequate glycemic control with metformin. METHODS: We performed a prospective, randomized study of 37 overweight or obese patients with T2DM who had inadequate glycemic control with metformin. The patients were treated with either exenatide or glargine for 16 weeks. Dual-energy X-ray absorptiometry was used to assess body composition. RESULTS: Post-intervention weight, body mass index (BMI), waist circumference, body mass, and fat mass were lower in patients treated with exenatide, while weight and BMI significantly increased with glargine. Reductions in weight, BMI, body fat mass, and percent fat mass (except for gynoid) were greater with exenatide than with glargine, and percent lean tissue (other than the limbs) increased with exenatide. In all body regions except for the limbs, fat mass decreased with exenatide to a greater extent than lean tissue. Glucose control, insulin resistance, and β-cell function were not different between the treatment groups. CONCLUSIONS: For overweight and obese patients whose T2DM was inadequately controlled with metformin, exenatide and glargine achieved similar improvements in glycemic control, insulin sensitivity, and β-cell function.However, exenatide produced better weight and fat mass reduction, which were beneficial for blood glucose control. Our findings may guide the selection of appropriate drugs for glycemic and weight control. TRIAL REGISTRATION: NCT02325960, registered 25 December 2014.