The Effect of Traumatic Brain Injury on the Gastrointestinal System: A Comprehensive Review

Area of Science:

• Neuroscience
• Gastroenterology
• Public Health

Background:

• Traumatic brain injury (TBI) presents a major public health challenge with diverse physical, cognitive, and behavioral consequences.
• A growing body of research indicates a complex, bidirectional interplay between brain injury and gastrointestinal health, termed the brain-gut axis.

Purpose of the Study:

• To conduct a comprehensive literature review on the relationship between TBI and gastrointestinal pathologies.
• To explore how TBI contributes to GI dysfunction and how gut health influences neurological recovery.

Main Methods:

• A systematic literature search was performed using PubMed, Scopus, and Cochrane databases from 2010 onwards.
• Human studies were screened using keywords related to TBI and gastrointestinal pathology.
• Data on study design, population, GI outcomes, and mechanisms were analyzed.

Main Results:

• TBI initiates secondary injury cascades, including neuroinflammation, dysautonomia, and gut microbiome dysbiosis.
• Common TBI-associated GI disorders include dysphagia, esophageal, gastric, and intestinal issues, alongside prevalent bowel dysfunction.
• Metabolic dysregulation post-TBI, such as malnutrition and altered glucose levels, exacerbates morbidity.

Conclusions:

• The gastrointestinal system plays a vital role in TBI recovery via immune modulation and nutrient absorption.
• Brain-gut axis dysfunction, characterized by altered motility, permeability, and inflammation, worsens secondary brain injury and neurological outcomes.
• Integrating GI dysfunction assessment and early enteral nutrition into TBI care is essential for improving recovery and reducing inflammation.