Proton magnetic resonance spectroscopy studies have concluded that changes in brain glutamatergic function could be associated with schizophrenia and the response to antipsychotic treatment. However, the relationship between altered glutamatergic function and clinical/demographic factors isn’t clear. This study aims to examine the associations of symptoms and characteristics of schizophrenia with brain glutamatergic metabolites.

This meta-analysis of individual participant-level data included a total of 45 proton magnetic resonance spectroscopy studies that measured glutamate levels (Glu) in patients with schizophrenia. The primary outcome of the study was the association of Glu, Glu plus glutamine (Glx), or total creatine (Cr) plus phosphocreatine levels in the medial frontal cortex (MFC) and medial temporal lobe (MTL) with the following schizophrenia characteristics: age, symptom severity, functioning, and antipsychotic medication dose.

The findings suggested that MFC Glu levels were lower in patients compared to healthy volunteers. Even though Cr levels appeared to be low in patients, the difference wasn’t significant. The findings further indicated that the MFC Glu level was inversely associated with age. In patients who took antipsychotic medication, the dosage was negatively associated with MFC Glu.

The research concluded that lower brain Glu levels in schizophrenia patients were associated with antipsychotic medication exposure.