Proton magnetic resonance spectroscopy measures related to short-term symptomatic outcome in chronic schizophrenia

• We performed a 1H MRS examination in schizophrenic patients before treatment.
• We evaluated a treatment outcome after approximately 40 days.
• Responders presented lower baseline prefrontal Glx level than non-responders.
• 1H MRS may be a useful tool for treatment outcome prediction.

IntroductionProton magnetic resonance spectroscopy (1H MRS) enables the evaluation of in vivo brain function. The purpose of the study was to compare 1H MRS measurements in schizophrenic patients, who were clinical responders after short-term antipsychotic treatment, with non-responders and healthy controls.MethodsWe investigated a group of 47 patients diagnosed with schizophrenia. Patients were examined twice – once after a period of at least 7 days without neuroleptics and the second time at least 4 weeks after therapy with stable doses of medication. The follow-up was available in 42 patients. Baseline MRS measurements of clinical responders were compared with non-responders and the group of healthy controls (N = 26). We assessed the following metabolite ratios: NAA (N-acetylaspartate), Glx (complex of GABA, glutamine and glutamate), Cho (choline) and mI (myo-inositol) to creatinine (Cr) in the left frontal and temporal lobes and the thalamus.ResultsResponders showed a significantly lower baseline frontal Glx/Cr level than non-responders. Both groups had a significantly lower NAA/Cr ratio in the frontal lobe than the controls, but only non-responders had a significantly lower NAA/Cr ratio in the thalamus.ConclusionsOur results confirm the relationship between the glutamatergic system and pathophysiology of schizophrenia and suggest a significant value of 1H MRS examination in the assessment of the future treatment effect.