Are heat-killed probiotics more effective than live ones on colon length shortness, disease activity index, and the histological score of an inflammatory bowel disease-induced murine model? A meta-analysis.

This study was conducted to compare the efficiency of heat-killed and live probiotics against colon length shortness, disease activity index (DAI), and the histological score of an inflammatory bowel disease (IBD) via a meta-analysis. In February 2022, the eligible papers were collected from four databases (Google Scholar, PubMed, ScienceDirect, and Scopus). Using common- and random-effects models, the effect sizes were estimated throughout the standardized mean difference. Forty-three papers were recorded for our meta-analysis, and the heterogeneity of the effect sizes was determined with Cochran's Q test, followed by meta-ANOVA and meta-regression analyses. The probiotics (live and heat-killed) had globally an improving or preventive effect on colon length shortness, DAI, and histological score. The sub-group analysis revealed that the heat-killed probiotics had statistically (P > .05) the same improving effect on colon length shortness, DAI, and histological score as live probiotics. In conclusion, this study suggested that live and heat-killed probiotics had a similar impact on IBD symptoms investigated in this study. The present outcomes would be a good base for researchers willing to further compare the effects of live and heat-killed probiotics on IBD.