Measurement of brain glutathione with magnetic Resonance spectroscopy in Schizophrenia-Spectrum disorders - A systematic review and Meta-Analysis.
Level 3 - non-randomized controlled study
Systematic review and meta-analysis of observational case-control neuroimaging studies
PubMed 37769980 · doi:10.1016/j.bbi.2023.09.017
What was done
A systematic review and meta-analysis evaluated 21 in vivo magnetic resonance spectroscopy (MRS) studies assessing brain glutathione levels in individuals with schizophrenia-spectrum disorders compared to healthy controls. The primary analysis examined medial prefrontal cortex glutathione concentrations, subgroup effects across clinical stages (such as stable schizophrenia), and potential confounding from spectroscopy methodology (e.g., voxel size, echo time) and publication year via meta-regression.
What was found
Across all included psychosis patients (N = 639) and controls (N = 704), medial prefrontal glutathione levels did not differ significantly (k = 21, d = -0.09, 95% CI -0.28 to 0.10, p = 0.37). In a subgroup of patients with stable schizophrenia, there was a small but statistically significant reduction in glutathione compared to controls (k = 14, d = -0.20, 95% CI -0.40 to -0.00, p = 0.05). Meta-regression demonstrated that older studies reported larger glutathione reductions, whereas technical parameters including voxel size and echo time had no significant effect.
Why it matters
These results clarify that medial prefrontal glutathione deficits are not a uniform biomarker across all stages of psychosis, but may be subtly present in chronic, stable schizophrenia.
Limits
The included literature consists entirely of observational, cross-sectional case-control imaging studies. The subgroup finding in stable schizophrenia reached only borderline statistical significance (p = 0.05). The abstract does not report data for brain regions outside the medial prefrontal cortex, nor does it quantify statistical heterogeneity (I²), medication exposure, or substance use.
Cited by
- supports Glutathione levels are low in serious mental illness.