Glutamatergic metabolite correlations with neuropsychological tests in first episode schizophrenia

Increased glutamatergic metabolites have been found in first episode schizophrenia. Although abnormal neuropsychological functioning has been demonstrated to be a core feature of schizophrenia, no studies have examined glutamatergic metabolites and neuropsychological function in drug na ve patients. The present study addressed whether higher levels of gluLamaLergic mcLabolftes would be associated with poorer neuropsychological performance and social funcLioning in first episode paLienLs. GluLarnaLergic concenLraLion esLimaLes were obtained from he left anterior cingulaLe codex (ACC) and Lhalarnus aL baseline and 10 months after LreaLmenL in 16 paLienLs with psychosis using 4.0T 1H magneLic resonance specLroscopy. A neuropsychological Les L baLLery was administered aL baseline and 1 year. In Lhe ACC, baseline gluLamine was associaLecl with performance on the Paced Auditory Serial AddiLion Task (PASAT). GluLamaLe aL 10 months was associaLed with Wisconsin Card SorLing Tesl. (WCST) errors and Trail Making Test-B duration. Glutamine at 10 months was positively associated with WCST errors and negatively associated with WCST categories completed. In the thalamus, baseline glutamine was negatively associated with performance on the PASAT. Thalamic glutamate at baseline showed a trend towards a negative association with social functioning at 5 years. Glutamatergic metabolites were associated with neuropsychological test deficits and impaired social functioning at 5-year follow-up in patients with first episode psychosis, findings suggestive of an association between glutamatergic alterations on neurotoxicity early in the course of schizophrenia. Crown Copyright (C) 2015 Published by Elsevier Ireland Ltd. All rights reserved.