Composition of gut microbiota and alcohol-related liver disease: A systematic review and meta-analysis

The intestinal microbiome has been identified as a key factor influencing the development and prognosis of alcohol-related liver disease (ARLD). This article aims to systematically review and meta-analyze the alterations in the gut microbiome associated with ARLD, providing a comprehensive overview of these changes.

PubMed, Embase, and Web of Science databases were systematically searched from January 1, 2015, to September 1, 2024, with the search limited to studies published in English and Chinese. Articles meeting the inclusion criteria-providing gut microbiota analysis and reporting changes in diversity and abundance-were selected through a two-stage screening process. Data extraction was conducted independently by two reviewers to ensure accuracy and reliability.

We compared gut microbiota differences between ARLD patients and healthy individuals, focusing on α-diversity, β-diversity, and microbial abundance. Among 17 studies, α-diversity indices showed a significant decrease in Shannon index (SMD=-0.63, 95 % CI= [-1.40, -0.14]), p < 0.001), Chao1 (SMD=-1.20, 95 % CI= [-1.67, -0.74], p = 0.022), and OTUs (SMD=-1.14, 95 % CI= [-1.55, -0.73], p = 0.010), with no significant differences observed in Simpson index, ACE, inverse Simpson, or Pielou evenness. Of 21 studies on β-diversity, 16 reported significant differences between ARLD and healthy controls. Most findings indicate a reduction in anti-inflammatory microorganisms and an enrichment of pro-inflammatory microorganisms in ARLD patients.

The study revealed that intestinal microbiome changes in ARLD patients are characterized by decreased microbial diversity, a reduction in anti-inflammatory microbiota, and an enrichment of pro-inflammatory bacteria. These findings highlight the intestinal microbiome as a promising target for potential ARLD treatment strategies.