Obesity, diabetes, and the metabolic syndrome: New challenges in antipsychotic drug therapy

Obesity and diabetes continue to be national health epidemics. Greater than 50% of adults in the United States are overweight, and > 17 million people have diabetes-one third of whom are not diagnosed. Diabetes ranks number I in direct health care costs of any disease category. Patients who suffer from schizophrenia may be at twice the risk of developing diabetes compared with the general population. Some new antipsychotic agents are among several types of medications that may potentially impair glucose metabolism. For example, studies have shown that people treated with clozapine and olanzapine have developed elevated fasting serum insulin levels, suggestive of insulin resistance. Insulin resistance may be a result of irregularities in the insulin action sequence and it may occur long before overt diabetes. The further study of the effects of medications on glucose metabolism and their mechanisms, therefore, is essential to developing better treatment regimens that minimize insulin resistance and avoid associated health risks such as obesity and diabetes.