Improving Diabetes Risk Factors in Persons With Schizophrenia or Bipolar Disorder by Switching to Ziprasidone

Improving Diabetes Risk Factors in Persons With Schizophrenia or Bipolar Disorder by Switching to Ziprasidone

Having a diagnosis of schizophrenia or bipolar disorder and being treated with certain of the newer antipsychotics are risk factors for development of diabetes. Subjects with these risk factors plus obesity and/or family history of diabetes who agree to study participation will undergo an oral glucose tolerance test. If the oral glucose tolerance test demonstrates that the subject is pre-diabetic (elevated glucose levels, but below the diabetic range), he/she will have his/her insulin resistance level measured, prior to random assignment to either stay on current antipsychotic medication or switch to ziprasidone. Insulin resistance will be measured again after four months. The primary hypothesis is that insulin resistance will decrease in those switched to ziprasidone relative to those continuing on their same antipsychotic medication.

Inclusion Criteria:

• Diagnosis of schizophrenia or schizoaffective disorder or bipolar disorder
• BMI>29.9 or family history of diabetes and/or abdominal circumference greater than 88 cm in women or 102 cm in men
• Pre-diabetic oral glucose tolerance test
• Current treatment with olanzapine, risperidone, paliperidone, or quetiapine, or combination of these
• Willing to switch to ziprasidone
• No psychiatric hospitalizations in past three months and judged by treating clinician to be suitable for antipsychotic medication switch
• Able to give informed consent to study

Exclusion Criteria:

• Judged to be currently suicidal, homicidal, or unable to cooperate with treatment
• Unstable serious medical illness
• Current use of drugs that interfere with glucose and fat metabolism (sulfonylureas, metformin, thiazolidinediones). The use of "statins" and fibrates will be allowed ONLY if stable dose for past 3 months.
• Current diagnosis of diabetes
• Fasting blood glucose >125 mg/dl