Probiotics for prevention of radiation-induced diarrhea: A meta-analysis of randomized controlled trials.

PloS one. 2017;12(6):e0178870

Plain language summary

Acute radiation-induced diarrhoea is a potentially fatal side effect of radiotherapy for abdominal or pelvic cancers. The mechanisms are not yet known, but effects of the radiation on the microbiota may be a factor and probiotic treatment may therefore be beneficial. The authors of this meta-analysis looked at randomised controlled trials of probiotics in the prevention of radiation-induced diarrhoea with probiotics (there were not enough trials to evaluate probiotics for the treatment of radiation-induced diarrhoea). Only six studies qualified for inclusion into this meta-analysis, with a total of 917 patients (490 receiving probiotics, 427 controls). Compared with placebo, patients receiving probiotics had a significantly lower risk of developing diarrhoea, but there was no significant reduction in anti-diarrhoea medication use or Bristol scale stool form. Most studies did not report adverse events from probiotic treatment. The meta-analysis was limited by several factors: variety of bacterial strains, dosages and timings used, differences in cancer treatment (dose of radiotherapy, radiotherapy alone or with chemotherapy), variability of patient populations and diseases, and diagnostic criteria for diarrhoea.

Abstract

BACKGROUND Radiotherapy is commonly used for abdominal or pelvic cancer, and patients receiving radiotherapy have a high risk developing to an acute radiation-induced diarrhea. Several previous studies have discussed the effect of probiotics on prevention of radiation-induced diarrhea, but the results are still inconsistent. OBJECTIVE We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the efficacy of probiotic supplementation for prevention the radiation-induced diarrhea. METHODS Relevant RCTs studies assessing the effect of probiotic supplementation on clinical outcomes compared with placebo were searched in PubMed, EMBASE, and the Cochrane Library databases (up to March 30 2016). Heterogeneity was assessed with I2 and H2, and publication bias was evaluated using sensitive analysis. RESULTS Six trials, a total of 917 participants (490 participants received prophylactic probiotics and 427 participants received placebo), were included in this meta-analysis. Compared with placebo, probiotics were associated with a lower incidence of radiation-induced diarrhea (RR: 0.55; 95% CI: 0.34-0.88; P = 0.01; I2: 87%; 95% CI: 75%-94%; H2: 2.8; 95% CI: 2.0-4.0). However, there is no significant difference in the anti-diarrheal medication use (RR: 0.68; 95% CI: 0.40-1.14; P = 0.14) or bristol scale on stool form (RR: 0.64; 95% CI: 0.35-1.17; P = 0.14). CONCLUSION Probiotics may be beneficial to prevent radiation-induced diarrhea in patients who suffered from abdominal or pelvic cancers during radiotherapy period.

Lifestyle medicine

Patient Centred Factors : Mediators/microbiota
Environmental Inputs : Radiation
Personal Lifestyle Factors : Not applicable
Functional Laboratory Testing : Not applicable
Bioactive Substances : probiotics

Methodological quality

Allocation concealment : Not applicable
Publication Type : Journal Article ; Meta-Analysis

Metadata