RESTING CEREBRAL GLUCOSE-METABOLISM IN FIRST-EPISODE AND PREVIOUSLY TREATED PATIENTS WITH SCHIZOPHRENIA RELATES TO CLINICAL-FEATURES

Background: Functional neuroimaging can elucidate brain dysfunction in schizophrenia. The frontal, temporolimbic, and diencephalic regions h ave been implicated. There is a lack of prospective samples of first-e pisode and previously treated patients followed up longitudinally. Met hods: Patients and controls (42 per group) were studied. Positron emis sion tomography with fluorodeoxyglucose, cross-registered with magneti c resonance imaging, measured metabolism. Scales assessed clinical fea tures, premorbid adjustment, and outcome. Results: There were no diffe rences between groups in whole-brain metabolism or regional ratios or in anterior-posterior gradients, but left midtemporal metabolism was r elatively higher in patients. This was pronounced in the negative and Schneiderian and absent in the paranoid subtypes. Higher metabolism an d lower relative left hemispheric values were associated with better p remorbid adjustment and outcome. A higher subcortical-cortical gradien t was noted in first-episode patients. Conclusions: There are no resti ng metabolic abnormalities in any brain region, but abnormal gradients are evident. These vary in subtypes, and laterality is associated wit h functioning. The results support the hypothesis of temporolimbic dis turbance in schizophrenia that is already present at the onset of illn ess.