Relationship between insulin resistance, dyslipidaemia and positive symptom in Chinese antipsychotic-naive first-episode patients with schizophrenia

Controversial results concerning insulin resistance and lipid metabolism have been reported in antipsychotic-naive first-episode psychosis (AN-FEP) patients with schizophrenia of different countries. We aimed at determining whether schizophrenia-related psychopathology was associated with insulin resistance and/or dyslipidaemia in Chinese patients with AN-FEP schizophrenia. A cross-sectional study was performed in Chinese patients newly diagnosed with schizophrenia (n = 49, antipsychotic-naïve or antipsychotic medications< 2 weeks) and healthy volunteers (n = 30). The serum levels of insulin and triglyceride levels as well as homeostasis model of assessment-insulin resistance (HOMA-IR) index were significantly increased in AN-FEP patients, when compared with healthy volunteers. The gender difference had a significant impact on the insulin resistance and dyslipidaemia in these AN-FEP subjects. Multiple linear regression analysis demonstrated that the severity of positive symptoms of schizophrenia was negatively related to insulin resistance. No difference of serum glucose level, total cholesterol content, body mass index (BMI) and smoking status was detected between patients with schizophrenia and healthy controls. In conclusion, Chinese AN-FEP patients were more prone to insulin resistance and dyslipidaemia as compared to the healthy population, which is negatively correlated to positive symptoms. The results may contribute to the understanding of the relationship between the glucose/lipidaemia metabolic dysfunction and the psychopathology in patients with schizophrenia.