The Effect of DHA Supplementation on Cognition in Patients with Bipolar Disorder: An Exploratory Randomized Control Trial

Abstract

Bipolar disorder (BD) is a severe mental disorder with a wide range of cognitive deficits, both in the euthymic and acute phase of the disease. Interestingly, in recent years, there has been a growing interest in investigating the impact of ω-3 polyunsaturated fatty acids on cognition in BD. In this context, the aim of this study is to evaluate the effect of docosahexaenoic acid (C22:6 ω-3, DHA) supplementation on cognitive performances in euthymic BD patients. This is an exploratory, single-centre, double-blind randomized controlled trial evaluating 12 weeks DHA supplementation (1250 mg daily) vs. a placebo (corn oil) in 31 euthymic BD patients compared to 15 healthy controls (HCs) on cognitive functions, assessed by the Brief Assessment of Cognition in Affective Disorder (BAC-A). Plasma levels of DHA were measured. After 12 weeks of treatment, no significant group differences were observed in all neuropsychological tests between the four groups, except for the emotion inhibition test, where HCs with DHA had higher scores compared to either BD with DHA (z = 3.9, p = 0.003) or BD with placebo (t = 3.7, p = 0.005). Although our results showed that DHA could be effective for ameliorating cognition in healthy subjects, future studies are still needed to clarify the impact of DHA on cognition in BD.

Importance of EPA and DHA Blood Levels in Brain Structure and Function

“…When intervention trials on parameters of cognition published up to 2015 were broken down according to dose of DHA used, it became apparent that trials using more than 600 mg DHA per day had positive results in terms of aspects of memory, executive function, or aspects of learning, while those using lower doses largely had neutral results [ 12 ]. However, more recently, both neutral and positive results were published with doses >600 mg DHA per day [ 119 , 120 , 121 , 122 , 123 , 124 , 125 ]. One trial found the improvement in executive function and verbal fluency to correlate with the increase of EPA in red cells, as well as improvements in pertinent brain structures [ 126 ].…”

Does Maternal Arachidonic Acid Influence the Neurodevelopmental Effects of Docosahexaenoic Acid?

“…But combined DHA and EPA supplementation for 6 weeks improved mania and depression among juvenile patients [233][234][235]. However, recent RCT found DHA has no role in improving the symptoms of bipolar disorder [15].…”

“…Intake of DHA improves attention deficit hyperactivity disorder (ADHD), bipolar disorder, schizophrenia, impulsive behavior, and other brain disorders [15,115,117].…”

“…DHA has significant neurobiochemical roles in ion channel and receptor functions, the release of neurotransmitters, synaptic plasticity, and gene expression in the neurons. suggest its roles in delaying cognitive decline and modulating psychiatric disorders [15]. In fact, DHA supplementation may ameliorate neurodegeneration and modulate behavioral symptoms in major neuropsychiatric disorders such as dementia, schizophrenia, and depression in adults [16].…”

Editorial: Progress in Translational Neuroimaging: Integrating Pathways, Systems, and Phenomenology in Neurology and Psychiatry

“…In particular, this Research Topic corroborated the fact that nowadays, we need further research on the genetic, neurobiological, and cognitive bases of major psychiatric disorders in order to better delineate different domains charactering commonalities and dissimilarities across different spectrum and continuum diagnostic prototypes ( 3 ). This will ultimately help us to have an evolute idea of how human brain impairments affect neuropsychological functions, behavioral characteristics, general functioning, outcome, and disease trajectory of our patients ( 4 ). We finally, last but not least, thank the estimated authors who contributed to the issue to allow us to have the privilege to coordinate and guest edit such a prestigious issue.…”