Omega-3 fatty acids ameliorate cognitive dysfunction in schizophrenia patients with metabolic syndrome

Wei Tang; Yewei Wang; Feikang Xu; Weixing Fan; Yaoyao Zhang; Kaili Fan; Weiping Wang; Yi Zhang; Chen Zhang

doi:10.1016/j.bbi.2020.04.034

Omega-3 fatty acids ameliorate cognitive dysfunction in schizophrenia patients with metabolic syndrome

Brain Behav Immun. 2020 Aug:88:529-534. doi: 10.1016/j.bbi.2020.04.034. Epub 2020 Apr 15.

Authors

Wei Tang¹, Yewei Wang², Feikang Xu³, Weixing Fan⁴, Yaoyao Zhang⁵, Kaili Fan⁵, Weiping Wang⁴, Yi Zhang³, Chen Zhang⁶

Affiliations

¹ Schizophrenia Program, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Psychiatry, The Affiliated Kangning Hospital of Wenzhou Medical University, Zhejiang, China.
² Schizophrenia Program, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
³ Schizophrenia Program, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
⁴ Department of Psychiatry, Jinhua Second Hospital, Jinhua, Zhejiang, China.
⁵ Department of Psychiatry, The Affiliated Kangning Hospital of Wenzhou Medical University, Zhejiang, China.
⁶ Schizophrenia Program, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China. Electronic address: zhangchen645@gmail.com.

PMID: 32304881
DOI: 10.1016/j.bbi.2020.04.034

Abstract

Our previous study showed that metabolic abnormalities reduced the levels of brain-derived neurotrophic factor (BDNF) and deteriorated cognitive performance in patients with schizophrenia. Inflammation may play a key role in this process. Omega-3 fatty acids have been documented to ameliorate inflammation. Therefore, we hypothesized that omega-3 fatty acids may be of value in enhancing BDNF levels and improving cognitive function in patients with schizophrenia with metabolic syndrome (MetS). We recruited 80 patients with both schizophrenia and MetS who received long-term olanzapine monotherapy. The enzyme-linked immunosorbent assay was used to measure the plasma levels of C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α). The patients were randomly assigned to the OMG-3 group (n = 40) or the placebo group (n = 40). Of the 80 patients who consented to the study, 72 completed this 12-week RCT. The primary outcome was the changes from baseline to 12 weeks in clinical characteristics and the levels of BDNF, CRP, IL-6 and TNF-α. There was a significant correlation between omega-3 fatty acid treatment and enhanced delayed memory factor in the RBANS assessment (F_group×time = 6.82; df = 1, 66; P = 0.01) when the patients completed this study. Along with cognitive improvement, omega-3 fatty acids enhanced BDNF (F_group×time = 4.93; df = 1, 66; P = 0.03) and reduced CRP (F_group×time = 17.11; df = 1, 66; P < 0.01), IL-6 (F_group×time = 9.71; df = 1, 66; P < 0.004) and TNF-α (F_group×time = 6.71; df = 1, 66; P = 0.012) levels after 12 weeks of treatment. The changes in BDNF levels are negatively correlated with the changes in TNF-α levels (r = -0.37, P = 0.03) but not with the changes in CRP and IL-6 levels. Our findings provide suggestive evidence that omega-3 fatty acids have beneficial effects on cognitive function in patients with MetS, which is paralleled by enhanced BDNF levels.

Keywords: Brain-derived neurotrophic factor; Cognitive function; Inflammation; Metabolic syndrome; Omega-3 fatty acid; Schizophrenia.

Publication types

Randomized Controlled Trial
Research Support, Non-U.S. Gov't

MeSH terms

Cognitive Dysfunction* / drug therapy
Fatty Acids, Omega-3 / therapeutic use*
Humans
Metabolic Syndrome* / complications
Metabolic Syndrome* / drug therapy
Olanzapine / therapeutic use
Schizophrenia* / complications
Schizophrenia* / drug therapy

Substances

Fatty Acids, Omega-3
Olanzapine