Additive efficacy and safety of probiotics in the treatment of ulcerative colitis: a systematic review and meta-analysis.

BACKGROUND: We aim to report the latest pooled analyses to evaluate the additive efficacy and safety of probiotics in the treatment of ulcerative colitis (UC).

METHODS: We systematically searched the relevant literature investigating the efficacy and/or safety of probiotics in patients with UC from PubMed, Embase and Web of Science up to January 2023. Two researchers independently screened the literature, extracted data, and evaluated the quality of the included studies according to the inclusion and exclusion criteria. Any discrepancies throughout these processes were solved by consensus. All statistical analyses were performed by Review Manager version 5.4 and Stata version 15.0.

RESULTS: A total of 13 articles were included in the pooled analyses, and the studies were all randomized controlled trials with a total of 930 patients. There were no significant differences between the probiotics and placebo groups concerning demographic and baseline characteristics. For patients with active UC, the probiotic group boosted the remission rate by 87% compared to the placebo group, but failed to reach a statistical difference (OR: 1.87; 95% CI 0.98, 3.57; P = 0.06, I2  = 67%); furthermore, there were no statistical differences in maintenance of clinical remission, clinical response, change in UCDAI scores, or mucosal healing outcomes in the probiotic group compared to the placebo group. For patients in clinical remission, the clinical relapse rates were significantly lower in the probiotic group than in the placebo group (OR: 0.34; 95% CI 0.14, 0.79; P = 0.01). Moreover, this study did not observe a significant difference between the two groups for general adverse events rate (OR: 1.98; 95% CI 0.69, 5.68; P = 0.20).

CONCLUSION: Probiotic-assisted therapy may be effective in inhibiting UC recurrence in patients in clinical remission without increasing the risk of treatment-related adverse events; furthermore, probiotics may increase the rate of clinical remission in patients with active UC. However, caution is needed when interpreting the clinical efficacy of probiotics in improving the clinical outcome of patients with active UC.