Although HIV antiretroviral medications have helped patients live longer, they have also been associated with side effects including insulin resistance and changes in body fat distribution. Changes in body fat distribution associated with HIV antiretroviral medications may result in increased fat in the abdomen, neck, and upper back, which is often called central fat deposition. HIV antiretroviral medications may also result in loss of fat in legs, arms, and face, which is often called peripheral fat atrophy.~This study will obtain preliminary data on the effect of 12 weeks of metformin on insulin sensitivity and hepatic and peripheral muscle fat in HIV-infected persons with insulin resistance and central fat deposition. Similarly, this study will obtain preliminary data on the effect of 12 weeks of pioglitazone on insulin sensitivity and hepatic and peripheral muscle fat in HIV-infected persons with insulin resistance and peripheral fat atrophy.~This study involves taking a drug that has been approved by the U.S. Food and Drug Administration (FDA) for use in humans for a period of 3 months.
The purpose of this study is to examine the relationship between insulin resistance and changes in body fat distribution in HIV-infected persons. This study measures insulin sensitivity, abdominal fat, and intramuscular fat in HIV-infected persons and examines the effect of an anti-diabetic drug (metformin or pioglitazone) on insulin sensitivity and body fat in this population.