1. Variability and magnitude of brain glutamate levels in schizophrenia: a meta and mega-analysis
- Author
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Kate Merritt, Robert McCutcheon, André Aleman, Sarah Ashley, Katherine Beck, Wolfgang Block, Oswald Bloemen, Faith Borgan, Christina Boules, Juan Bustillo, Aristides Capizzano, Jennifer Coughlin, Anthony David, Camilo de la Fuente-Sandoval, Arsime Demjaha, Kara Dempster, Kim Do, Fei Du, Peter Falkai, Beata Galińska-Skok, Jürgen Gallinat, Charles Gasparovic, Cedric E Ginestet, Naoki Goto, Ariel Graff-Guerrero, Beng-Choon Ho, Oliver Howes, Sameer Jauhar, Peter Jeon, Tadafumi Kato, Charles Kaufmann, Lawrence Kegeles, Matcheri Keshavan, Sang-Young Kim, Bridget King, Hiroshi Kunugi, John Lauriello, Pablo León-Ortiz, Edith Liemburg, Meghan Mcilwain, Gemma Modinos, Elias Mouchlianitis, Jun Nakamura, Igor Nenadic, Dost Öngür, Miho Ota, Lena Palaniyappan, Christos Pantelis, Tulsi Patel, Eric Plitman, Sotirios Posporelis, Scot Purdon, Jürgen Reichenbach, Perry Renshaw, Francisco Reyes-Madrigal, Bruce Russell, Akira Sawa, Martin Schaefer, Dikoma Shungu, Stefan Smesny, Jeffrey Stanley, James Stone, Agata Szulc, Reggie Taylor, Katharine Thakkar, Jean Théberge, Philip Tibbo, Thérèse van Amelsvoort, Jerzy Walecki, Peter Williamson, Stephen Wood, Lijing Xin, Hidenori Yamasue, Philip McGuire, and Alice Egerton
- Subjects
anterior cingulate cortex ,dorsolateral prefrontal cortex ,quality ,antipsychotic treatment ,psychosis ,magnetic-resonance spectroscopy ,dopamine ,gamma-aminobutyric-acid ,in-vivo ,metaanalysis - Abstract
Glutamatergic dysfunction is implicated in the pathoaetiology of schizophrenia, but this may vary in extent between patients. It is unclear whether inter-individual variability in glutamate is greater in schizophrenia than the general population. We conducted meta-analyses to assess (1) variability of glutamate measures in patients relative to controls, using the log coefficient of variation ratio (CVR); (2) standardised mean differences (SMD) using Hedges g; (3) modal distribution of individual-level glutamate data using Hartigan’s unimodality dip test. MEDLINE and EMBASE databases were searched from inception to October 2021 for proton magnetic resonance spectroscopy (1H-MRS) studies reporting glutamate, glutamine or Glx in schizophrenia patients compared to controls. 116 studies reporting on 7,844 patients and 7,305 controls were included. Compared with controls, patients demonstrated greater variability in glutamatergic metabolites in the medial frontal cortex (MFC, glutamate: CVR = 0.15, p