Proton magnetic resonance spectroscopy changes after antipsychotic treatment

Proton magnetic resonance spectroscopy ((1)H MRS) enables the observation of brain function in vivo. Several brain metabolites can be measured by the means of (1)H MRS: N-acetylaspartate (NAA), choline containing compounds (Cho), myo-inositol (mI) and glutamate (Glu), glutamine (Gln) and GABA (together as Glx complex or separately). (1)H MRS measures have been found to be abnormal in psychotic disorders such as schizophrenia. Here we specifically review the influence exerted by antipsychotic drugs on brain metabolism, as detected by (1)H MRS. We systematically reviewed the available literature and uncovered 27 studies, 16 before-after treatment and 11 cross-sectional. Most of them addressed the effects of antipsychotics in schizophrenia and mainly focusing on NAA alterations. Follow up studies indicated antipsychotic drugs may act by increasing NAA levels in selected brain areas (the frontal lobe and thalamus), especially during the short-time observation. This phenomenon seems to vanish after longer observation. Other studies indicated that glutamate measures are decreasing along with the duration of the disease, suggesting both a neurodegenerative process present in schizophrenic brain as well as an influence of antipsychotics. The above results were reviewed according to the most recent theories in the field accounting for the impact of antipsychotics (1)HMRS measures.