Observation of Metabolic Changes in Chronic Schizophrenia After Neuroleptic Treatment by In Vivo Hydrogen Magnetic Resonance Spectroscopy

RATIONALE AND OBJECTIVES: The authors investigate: (1) whether there is a lateral effect of hydrogen (1H) magnetic resonance (MR) spectroscopy observable metabolite ratios between the right and the left prefrontal lobe in chronic schizophrenia; (2) whether there is a change of proton metabolite ratios in chronic schizophrenia after neuroleptic treatment; (3) whether there is a relation between changes in 1H MR spectra and the clinical assessment of Brief Psychiatric Rating Scale (BPRS); and (4) to investigate a hypofrontality hypothesis in schizophrenia in terms of neurochemical aspects. METHODS: Localized in vivo 1H MR spectroscopy was used to measure the metabolite levels in the prefrontal lobes of control persons (n = 20) and of chronic patients before and after neuroleptic treatment (n = 34). The MR spectra of 8 cm3 voxels were compared with clinical assessment of BPRS in each subject. RESULTS: No significant metabolic lateral effect was established in both schizophrenia and control groups (P > 0.05). After neuroleptic treatment, chronic schizophrenic patients generally demonstrated a decrease of the complex of gamma-aminobutyric acid (GABA) and glutamate (Glu) containing (GABA + Glu)/creatine (Cr) ratio. CONCLUSIONS: The current follow-up 1H MR spectroscopy study shows a significant correlation between alterations of (GABA + Glu)/Cr ratio and BPRS, and supports a hypofrontality hypothesis in chronic schizophrenia. The reduction of (GABA + Glu)/Cr ratio after neuroleptic treatment may implicate the recovery of normal neuronal function in neurotransmitters. In vivo 1H MR spectroscopy may be a useful modality in follow-up evaluation of neuroleptic treatment in chronic schizophrenia.