Gut-Brain Axis-Mediated Cognitive Impairment in Bipolar Disorder: Mechanisms and Therapeutic Implications

Abstract

Gut-brain axis dysfunction can have long-term repercussions on cognitive function and psychosocial well-being in individuals with bipolar disorder. Gut microbiota alterations are a key factor affected by this dysfunction, as they contribute to neuroinflammation, neurotransmitter imbalances, and blood-brain barrier permeability associated with cognitive deficits. Adults with bipolar disorder often experience persistent cognitive impairments, resulting in functional limitations. The objective of the study was to review existing research on the relationship between gut-brain axis dysfunction and cognitive impairment in bipolar disorder. A secondary research design using a narrative literature review was adopted. Peer-reviewed articles and scholarly sources were collected from databases such as Google Scholar and PubMed. Relevant studies were analyzed thematically. An assessment of the existing evidence reveals a consistent unfavorable link between gut dysbiosis and cognitive impairment in bipolar disorder. Individuals with bipolar disorder exhibit reduced microbial diversity, decreases in beneficial bacteria like Faecalibacterium, Prevotella, and Roseburia, and increases in pro-inflammatory taxa, leading to deficits in attention, processing speed, memory, and executive function. According to research, addressing gut dysbiosis through probiotics, psychobiotics, and anti-inflammatory diets correlates with reduced inflammation, improved cognitive resilience, decreased neuroinflammation, and enhanced post-treatment functioning.