Differential Effects of Metformin and Troglitazone on Cardiovascular Risk Factors in Patients With Type 2 Diabetes

Differential Effects of Metformin and Troglitazone on Cardiovascular Risk Factors in Patients With Type 2 Diabetes Neelima V. Chu , MD 1 , Alice P. S. Kong , MRCP 1 , Dennis D. Kim , MD 1 , Debra Armstrong , RN 1 , Sunita Baxi , MD 1 , Reena Deutsch , PHD 2 , Michael Caulfield , PHD 3 , Sunder R. Mudaliar , MD, MRCP 1 , Richard Reitz , MD 3 , Robert R. Henry , MD, FRCP 1 and Peter D. Reaven , MD 4 1 Department of Endocrinology and Metabolism, VA San Diego Healthcare System/University of California, San Diego, California 2 University of California, San Diego, San Diego, California 3 Quest Diagnostics, San Juan Capistrano, California 4 VA Medical Center, Phoenix, Arizona Abstract OBJECTIVE —Traditional cardiovascular risk factors (CVRF) only partly explain the excessive risk of cardiovascular disease in patients with type 2 diabetes. There is now an increasing appreciation for many novel CVRF that occur largely as a result of insulin resistance and hyperinsulinemia. Therefore, we investigated whether diabetes medications that vary in their mechanism of action and ability to reduce insulin resistance may differ in their effects on both traditional and novel CVRF. RESEARCH DESIGN AND METHODS —We compared the addition of metformin or troglitazone therapy on CVRF in 22 subjects with type 2 diabetes who remained in poor glycemic control (with HbA 1c >8.5%) while taking glyburide 10 mg twice daily. Subjects were initially randomized to either metformin 850 mg once daily or troglitazone 200 mg once daily. Both medications were then titrated upward as needed to achieve fasting plasma glucose