BACKGROUND Our aim was to study the frequency of metabolic syndrome and associated factors in patients with schizophrenia. METHOD The study group consisted of 35 outpatients with long-term schizophrenia defined by DSM-IV criteria. Patients were assessed for the presence of metabolic syndrome, which was defined by the criteria of the National Cholesterol Education Program. All patients were on antipsychotic medication. Data were collected from Jan. 1, 2001, to Aug. 30, 2001. RESULTS Metabolic syndrome was found in 37% (N = 13) of the patients, and it was associated inversely with the total daily dose of, but not with any specific type of, antipsychotic drug. CONCLUSION The results suggest that metabolic syndrome is common among patients with schizophrenia, and it may be far more common than in general populations.