Body Mass Index (BMI) and Metabolic Changes Following Switch to Aripiprazole From Olanzapine, Risperidone and Quetiapine

Weight gain is a serious, common side effect of many antipsychotic medications. On average, the highest amounts of weight gain are found to occur in people taking clozaril and olanzapine, but with significant weight gain occuring in those on the other atypical antipsychotics as well. We, the researchers at the University of North Carolina, propose an open-label observational, pilot study of the changes in weight, BMI, body composition, and lipids, glucose, insulin and other metabolic parameters occurring in subjects as they switch from treatment with olanzapine, risperidone or quetiapine to aripiprazole. This medication switch will be determined prior to their entering this study by their treating psychiatrist. We also will determine resting energy expenditure (REE) and respiratory quotient (RQ) as measured by metabolic cart to determine if either energy expenditure or the propensity to store energy as fat may be involved in any changes to weight that are detected. Food intake, hunger, and physical activity will also be assessed.