Probiotics for the prevention of antibiotic-associated diarrhea – an umbrella review of meta-analyses of randomized controlled trials

Introduction and aim. Antibiotic therapies induce diarrhea by disrupting the intestinal microbiota, prompting research into probiotics to prevent antibiotic-associated diarrhea (AAD). The aim of this study was to systematically identify and summarize meta-analyses of randomized controlled trials (RCT) on probiotics for AAD prevention. Material and methods. Databases including PubMed, EMBASE, Epistemonikos, and the Cochrane Database were searched up to December 11, 2023. Systematic reviews and meta-analyses of RCTs on probiotics for AAD prevention in any age group were included. Meta-analyses were re-performed to calculate pooled risk ratios (RR) with 95% confidence intervals (CI). Evidence quality was assessed using GRADE criteria. Analysis of the literature. The review included 16 articles with 39 unique meta-analyses. Probiotics reduced AAD risk across various groups: adults (RR 0.47, 95% CI 0.40–0.56), all ages (RR 0.58, 95% CI 0.50–0.68), and outpatients (RR 0.49, 95% CI 0.36 0.66) with a moderate level of evidence. For the use of any probiotics in pediatrics, the initial high-quality evidence (RR 0.48, 95% CI 0.44–0.63) was downgraded to moderate after a sensitivity analysis excluding small studies. Conclusion. Probiotics are beneficial in preventing AAD, but evidence quality varies from low to moderate. High-quality trials are needed to identify the most effective probiotic species and strains, dosages, and target patient populations.