Quantitative Alterations in Short-Chain Fatty Acids in Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

Abstract

Background: Reduced short-chain fatty acids (SCFAs) in inflammatory bowel disease (IBD) impair the gut barrier and immune function, promoting inflammation and highlighting microbiome-targeted therapies’ therapeutic potential. The purpose of this meta-analysis was to study the changes in SCFAs in IBD and their potential role in the occurrence and development of IBD. Methods: The analysis employed a random-effects model to assess the standardized mean difference (SMD) with a 95% confidence interval. A literature search was conducted in databases from 2014 to 20 July 2024 to identify studies investigating SCFAs in IBD. Results: Subgroup analyses revealed a significant reduction in fecal SCFA levels—specifically butyrate, acetate, and propionate—in all IBD subgroups compared to healthy controls. Active IBD showed a greater decrease in butyrate (p = 0.004), and UC showed a notable reduction in propionate (p = 0.03). When comparing UC and CD, differences were observed mainly in propionate (SMD = −0.76, p = 0.00001). Dietary interventions in IBD patients led to increased SCFA levels, with butyrate showing the most improvement (SMD = 1.03), suggesting the potential therapeutic value of dietary modulation. Conclusions: In conclusion, this meta-analysis demonstrates a significant reduction in fecal SCFA levels in patients with IBD, particularly during active phases of the disease and most markedly in CD.

Keywords

• short-chain fatty acid
• butyrate
• acetate
• propionate
• inflammatory bowel disease
• Crohn’s disease