Prebiotics, probiotics, and synbiotics therapy in critically ill patients: a systematic review and network meta-analysis
In brief
Synbiotics halve gastrointestinal symptom risk in critically ill patients
In a network meta-analysis of 33 trials with 5,073 ICU adults, synbiotics reduced GI symptoms by about 48% compared with usual care, while prebiotics lowered risk by roughly one-third; probiotics showed a non-significant trend. No single formulation proved superior, and benefits may vary between medical and surgical ICU settings, warranting cautious interpretation.
- Journal
- Annals of intensive care (Q1)
- Published
- 4 August 2026
- Study design
- Systematic review / meta-analysis of RCTs
- Evidence level
- Level 1, High (CEBM 1a)
- Authors
- Junji Hatakeyama, Ryo Yamamoto, Minoru Yoshida, Kohei Yamada, Kazushige Inoue, Takayuki Irahara, et al.
- PMID
- 42633334
- DOI
- 10.1016/j.aicoj.2026.100130
Why clinicians should know about it
- Picked for Critical Care and Intensive Care Medicine (top studies of the week, 30 August 2026): Network meta-analysis of pre‑/pro‑/synbiotics in critically ill patients
Abstract
BACKGROUND: Critically ill patients frequently develop intestinal dysbiosis, leading to gastrointestinal (GI) symptoms and infectious complications. No network meta-analysis (NMA) has compared the relative effectiveness of prebiotics, probiotics, and synbiotics for reducing the risk of GI symptoms in critically ill patients. OBJECTIVE: This study aimed to evaluate their comparative effects in preventing GI symptoms and improving clinical outcomes. METHODS: MEDLINE, CENTRAL, and Web of Science were searched through June 2025. Eligible randomized controlled trials enrolled critically ill adults and compared prebiotics, probiotics, or synbiotics with controls (placebo or usual care). The primary outcome was GI symptom incidence. Secondary outcomes included mortality, intensive care unit (ICU) length of stay, mechanical ventilation duration, infectious complications, and adverse events. A frequentist random-effects NMA was conducted. Treatment rankings were exploratory, and certainty of evidence was not formally assessed. RESULTS: Thirty-three randomized controlled trials involving 5,073 patients were included in the analysis of GI symptoms. Compared with control, synbiotics significantly reduced the risk of GI symptoms (risk ratio [RR] 0.52; 95% confidence interval [CI]: 0.35 to 0.77), as did prebiotics (RR 0.66; 95% CI: 0.49 to 0.87). Probiotics produced a similar directional effect, but the difference was not statistically significant (RR 0.81; 95% CI: 0.60 to 1.10). No significant differences were found between the active interventions. Subgroup analyses suggested differences according to the ICU population. Among medical intensive care patients, prebiotics were associated with a lower risk of GI symptoms than control, whereas probiotics and synbiotics were associated with a lower risk among surgical intensive care patients. CONCLUSIONS: Synbiotics and prebiotics were associated with a significantly lower risk of gastrointestinal symptoms in critically ill patients, whereas probiotics showed a similar but statistically nonsignificant effect. No active intervention was significantly superior to another. The findings suggest that the relative benefits of these interventions may differ between medical and surgical intensive care populations. Nevertheless, the results should be interpreted cautiously because certainty of evidence was not formally assessed.PROSPERO registration number: CRD420251015729; https://www.crd.york.ac.uk/PROSPERO/view/CRD420251015729.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.