Elevation of CSF somatostatin concentrations in mania

OBJECTIVE: The aim of this study was to compare levels of CSF somatostatin (somatotropin release-inhibiting factor) in drug-free patients with different major psychiatric disorders. METHOD: CSF somatostatin concentrations were measured in 66 drug-free inpatients with Research Diagnostic Criteria diagnoses of schizophrenia, major depressive disorder, manic disorder, or schizoaffective disorder. RESULTS: In comparison with both the patients with schizophrenia and the patients with schizoaffective disorder, the manic patients had markedly elevated CSF somatostatin concentrations. The depressed patients had significantly higher levels than the schizophrenic patients. CONCLUSIONS: Mania is associated with relatively higher CSF somatostatin concentrations.