Oral glucose tolerance tests in schizophrenic patients treated with antipsychotics

Objective. –A recent consensus conference has proposed guidelines for the monitoring for diabetes in patients with schizophrenia and also
identifies the need of long-term prospective studies.
Method. – A large scale prospective study on metabolic risks of antipsychotic medication is currently ongoing. At baseline, patients get a
full laboratory screening, ECG and an oral glucose tolerance test (OGTT). Baseline data on 100 non-diabetic patients at study inclusion and
stable on medication for at least 6 months are presented.
Results. – Glucose abnormalities are found in 22% of patients at baseline.A monitoring protocol based only on fasting glucose would not
have detected 63.6% of these patients with classifiable glucose abnormalities in our sample. Fasting insulin and measures for insulin resistance
have a high predictive value for abnormalities late in the OGTT.
Conclusion. – Already at baseline, metabolic problems are frequently present in patients with schizophrenia treated with antipsychotics.
Adding assessment of fasting insulin in a monitoring protocol improves detection of glucose abnormalities late in an OGTT.