Background: Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease worldwide. The pathogenesis of NAFLD is complex and multifactorial. There is growing evidence that altered gut microbiota plays a key role in NAFLD progression. Probiotics/synbiotics, by modifying gut microbiota, may be a promising treatment choice for NAFLD management.
Aim: The aim of this study was to study the effect of probiotics/synbiotics on various laboratory and radiographic parameters in NAFLD management.
Materials and methods: A systematic review and meta-analysis were carried out according to Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. We searched PubMed, Medline, and Google Scholar for randomized-controlled trials that studied the role of probiotics/synbiotics in NAFLD. The primary outcome was change in baseline alanine aminotransferase and aspartate aminotransferase in the treatment arm. We used a random-effects model and inverse variance for the continuous data to estimate the mean difference (MD) and the standard mean difference (SMD) in RevMan Version 5.3.
Results: We included 12 randomized-controlled trials for analysis. The intervention arm, which comprised of the probiotic and/or the synbiotic arm, showed a significant improvement in alanine aminotransferase levels, MD=-13.93, confidence interval (CI)=-20.20 to -7.66, P value of less than 0.0001, I=92% and aspartate aminotransferase levels MD=-11.45, CI=-15.15 to -7.74, P value of less than 0.00001, I=91%. There was a reduction in high-sensitivity C-reactive protein levels in the intervention arm, SMD=-0.68, CI=-1.10 to -0.26, P value of 0.001, I=0%. The liver fibrosis score improved in the intervention arm, MD=-0.71, CI=-0.81 to -0.61, P value less than 0.00001, I=0%.
Conclusion: Probiotic/synbiotic use improves aminotransaminase levels and reduces proinflammatory marker high-sensitivity C-reactive protein and liver fibrosis in NAFLD patients.