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 (H-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.