Work

Effects of faecal microbiota transplantation on glycaemic outcomes in adults with metabolic disorders: a systematic review and meta-analysis of randomised controlled trials

Year: 2026

Type: review

Study designs: Systematic Review, Meta-Analysis

Abstract: Background: Faecal microbiota transplantation (FMT) may improve glucose metabolism, but findings from randomised trials and previous meta-analyses are inconsistent. We evaluated the effects of FMT on glycaemic outcomes in adults with type 2 diabetes, prediabetes, insulin resistance or related metabolic disorders. Methods: We searched PubMed and Scopus for English-language randomised controlled trials published from January 2000 to May 2026. The primary outcome was change from baseline in HOMA-IR. Secondary outcomes included HbA1c, fasting glucose and clamp-derived peripheral insulin sensitivity. Random-effects meta-analyses used Paule-Mandel estimation with Hartung-Knapp-Sidik-Jonkman confidence intervals. Sensitivity analyses evaluated comparator type, data reconstruction, the assumed baseline-follow-up correlation and individual-study influence. Risk of bias was assessed using RoB 2. Results: = 72%). The sensitivity analysis combining HOMA-IR and HOMA2-IR also produced a non-significant result (MD, -1.11; 95% CI [-2.50, 0.29]). HbA1c data were sparse and were not pooled across comparator types. Clamp-derived findings suggested a possible donor-phenotype effect but remained inconclusive. The certainty of evidence was very low for HOMA-IR and HbA1c and low for peripheral insulin sensitivity. Conclusions: FMT did not demonstrate a clear benefit for glycaemic outcomes. The estimates were imprecise, heterogeneous and influenced by comparator design. Larger trials with standardised outcomes and predefined donor phenotypes are required.

Source: Frontiers in Medicine

DOI: 10.3389/fmed.2026.1983162