Probiotics as a Coadjuvant Factor in Active or Quiescent Inflammatory Bowel Disease of Adults—A Meta-Analytical Study

(1) Background: Inflammatory bowel diseases are pathologies of unknown etiology and auto-immune pathogenia. The use of probiotics is studied in order to increase the arsenal of treatments. The aim was to assess the efficacy of the probiotics in these diseases in the active or quiescent phases; (2) Methods: A systematic review with meta-analysis was performed by an exhaustive bibliographic search in Medline, Cinahl, Embase, Scopus, Web of Science, and Cochrane Library. The inclusion criteria were studies of more than 10 years, English/Spanish, clinical trials, and involving human beings. Relative risk was used to compare efficacy, which was meta-analyzed using a fixed effects model. Heterogeneity was evaluated with the Higgins I(2) test; (3) Results: Nineteen studies were included in the systematic review and 17 in the meta-analysis, with a total of 1537 patients (n(experimental group) = 762; n(placebo group) = 775). There are significant remission differences in ulcerative colitis (relative risk (RR) = 0.81; 95% CI = 0.72–0.91; I(2) = 32%; p = 0.16). However, no significant differences were found in the use of probiotics for the prevention of ulcerative colitis, and for the remission of Crohn’s disease; (4) Conclusions: There are data showing an additional beneficial effect of probiotics on active ulcerative colitis. More and better studies are needed which assess its possible therapeutic efficacy for quiescent ulcerative colitis and for Crohn’s disease.