Gut-brain axis: biological correlations between inflammatory bowel disease and anxiety or depressive disorders - a scoping review of reviews.

OBJECTIVE

The bidirectional communication between the nervous system and the gastrointestinal tract plays a crucial role in maintaining homeostatic balance.The present study aims to understand the gut-brain axis and how this complex interaction relates to inflammatory bowel disease and the development of anxious and depressive symptoms. METHOD: The search for articles was conducted in the MEDLINE, LILACS, and Cochrane databases. Reviews published between 2009 and 2025 that addressed the gut-brain interaction with a focus on the development of inflammatory bowel disease (IBD) and anxious and/or depressive signs were included. Incomplete studies and those that addressed only one aspect were not selected.

RESULTS

The search resulted in 87 studies; after four selection stages, 15 articles remained according to the inclusion and exclusion criteria. The highest number of publications was from the period of 2021 to 2024. The level of evidence collected consistently reported that patients with IBD were more likely to develop depressive and/or anxiety symptoms. Studies further indicate that inflammatory markers, including C-reactive protein (CRP), explain a large part of the risk for psychiatric conditions.

CONCLUSION

The gut-brain axis should be understood as a potential factor in the development of mood disorders (anxiety and depression) in patients with IBD, due to the shared dysbiotic and immunological characteristics. By providing a comprehensive view of this complex bidirectional interconnection, the clinical significance of this association is reiterated, as well as the urgency to deepen the understanding of its pathophysiology. CLINICAL TRIAL NUMBER: Not applicable.