Proton magnetic resonance spectroscopy of the anterior cingulate gyrus, insular cortex and thalamus in schizophrenia associated with idiopathic unconjugated hyperbilirubinemia (Gilbert's syndrome).

Objective: To examine whether patients with schizophrenia associated with idiopathic unconjugated hyperbilirubinemia (Gilbert's syndrome [GS]) have specific changes in brain metabolism. Methods: We applied proton magnetic resonance spectroscopy (1H-MRS) to the anterior cingulate gyrus, insular cortex and thalamus of patients with schizophrenia and GS (n=15) or without GS (n=15), all diagnosed with schizophrenia according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV), and healthy subjects (n=20). Results: In the anterior cingulate gyrus, patients with schizophrenia and GS showed significant decreases in N-acetyl aspartate/creatine- phosphocreatinine (NAA/Cr), choline/creatine-phosphocreatinine (Cho/ Cr) and myoinositol/creatine-phosphocreatinine (ml/Cr) ratios compared with healthy subjects and compared with patients with schizophrenia without GS. Patients with schizophrenia without GS also showed significant decreases in NAA/Cr, Cho/Cr and ml/Cr compared with healthy subjects. In the insular cortex, patients with schizophrenia and GS showed significant decreases in NAA/Cr, Cho/Cr and ml/Cr compared with healthy subjects and compared with patients with schizophrenia without GS. Patients with schizophrenia without GS also showed significant decreases in NAA/Cr, Cho/Cr and ml/Cr compared with healthy subjects. In the thalamus, patients with schizophrenia and GS showed significant decreases in NAA/Cr, Cho/ Cr and ml/Cr compared with healthy subjects, whereas patients with schizophrenia without GS only showed a significant decrease in ml/Cr compared with healthy subjects. Conclusions: Our findings suggest that brain metabolism is more severely compromised in the subtype of schizophrenia with GS.