Kynurenic Acid in Schizophrenia: A Systematic Review and Meta-analysis

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#adult #female #humans #kynurenic-acid #male

Kynurenic Acid in Schizophrenia: A Systematic Review and Meta-analysis

Plitman et al., 2017 | Schizophr Bull | Meta Analysis

Citation

Plitman Eric, Iwata Yusuke, ... Graff-Guerrero Ariel. Kynurenic Acid in Schizophrenia: A Systematic Review and Meta-analysis. Schizophr Bull. 2017-Jul-01;43(4):764-777. doi:10.1093/schbul/sbw221

Abstract

Kynurenic acid (KYNA) is an endogenous antagonist of N-methyl-D-aspartate and α7 nicotinic acetylcholine receptors that is derived from astrocytes as part of the kynurenine pathway of tryptophan degradation. Evidence suggests that abnormal KYNA levels are involved in the pathophysiology of schizophrenia. However, this has never been assessed through a meta-analysis. A literature search was conducted through Ovid using Embase, Medline, and PsycINFO databases (last search: December 2016) with the search terms: (kynuren or KYNA) and (schizophreni or psychosis). English language studies measuring KYNA levels using any method in patients with schizophrenia and healthy controls (HCs) were identified. Standardized mean differences (SMDs) were calculated to determine differences in KYNA levels between groups. Subgroup analyses were separately performed for nonoverlapping participant samples, KYNA measurement techniques, and KYNA sample source. The influences of patients' age, antipsychotic status (%medicated), and sex (%male) on study SMDs were assessed through a meta-regression. Thirteen studies were deemed eligible for inclusion in the meta-analysis. In the main analysis, KYNA levels were elevated in the patient group. Subgroup analyses demonstrated that KYNA levels were increased in nonoverlapping participant samples, and centrally (cerebrospinal fluid and brain tissue) but not peripherally. Patients' age, %medicated, and %male were each positively associated with study SMDs. Overall, KYNA levels are increased in patients with schizophrenia, specifically within the central nervous system. An improved understanding of KYNA in patients with schizophrenia may contribute to the development of novel diagnostic approaches and therapeutic strategies.

Key Findings

An improved understanding of KYNA in patients with schizophrenia may contribute to the development of novel diagnostic approaches and therapeutic strategies.

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population schizophrenia and healthy controls
Sample Size See abstract
Age Range See abstract
Condition See abstract

MeSH Terms

  • Adult
  • Female
  • Humans
  • Kynurenic Acid
  • Male
  • Schizophrenia

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Meta-Analysis, Systematic Review
  • Vertical: niacin

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09