Helicobacter pylori (Hp) chronic infection is increasing worldwide and is involved in the pathogenesis of chronic gastritis, peptic ulcers, and gastric cancer. Eradication of the bacterium through proton-pump inhibitor (PPI)-based triple therapy (PPI, amoxicillin and either clarithromycin or metronidazole and clarithromycin) or bismuth-based quadruple therapy (bismuth added to the standard twice-daily PPI-based triple therapy) has recently decreased, mainly due to antibiotic resistance and drug-related adverse effects. Although several clinical trials (here; here; here) have reported a higher eradication rate and lower incidence of adverse events in Hp eradication therapy when patients are supplemented with probiotics, their comparative efficacy varies and it is still unknown which probiotic strain, dose and treatment duration is the most effective.
A recent systematic review and meta-analysis, led by Dr. Qiu Zhao from the Department of Gastroenterology at the Zhongnan Hospital of Wuhan University in China, has found that probiotic supplementation is associated with better rates of success in Hp eradication therapy, and fewer adverse events, with single and multiple species showing comparable results.
The researchers identified 140 studies (44 English and 96 Chinese) including a total of 20,215 patients. More than 10 kinds of probiotics or combinations (mainly Lactobacillus, Bacillus, Clostridium butyricum, Saccharomyces boulardii, Streptococcus lactis, Bifidobacterium and Enterococcus) were included in the studies. Selection criteria included: 1) Clinical trials that examined the efficacy of probiotics as supplemented in triple therapy, sequential therapy, or quadruple therapy for Hp infection; 2) Mean age of participants was greater than 18; 3) All patients were diagnosed with Hp infection (by urea breath test, histology, enzyme-linked immunosorbent assay, rapid urease test, culture, or Hp antigen test); and 4) Both the probiotic group and the control group shared the same treatment for Hp eradication.
Probiotic supplementation increased the efficacy of Hp eradication (84.1% in probiotic group versus 70.5% in control group) and decreased the incidence of adverse effects (14.1% in probiotic group versus 30.1% in control/no treatment group), but significance was only achieved in a subgroup analysis for some Hp eradication strategies. The exceptions were Lactobacillus reuteri or L. rhamnosus in 7-day triple therapy and Bifidobacterium in 14-day triple therapy; these were ineffective in terms of eradication rates.
Regarding the comparative efficacy of different probiotic strains, in Hp triple eradication therapy, all probiotics showed similar efficacy and combined probiotics did not show a better efficacy or tolerance than single species. The authors explained this by referring to common mechanisms of probiotics in reducing adverse events, potentially through antioxidant and anti-inflammatory effects, but this remains inconclusive and speculative.
In conclusion, probiotic supplementation may increase the efficacy of Hp eradication therapy and decrease the incidence of drug-related adverse effects. Further large prospective clinical trials will give a clearer picture regarding whether and which probiotics can be used routinely in clinical practice for improving the efficacy of Hp eradication therapies and decreasing the incidence of adverse events.
Wang F, Feng J, Chen P, et al. Probiotics in Helicobacter pylori eradication therapy: systematic review and network meta-analysis. Clin Res Hepatol Gastroenterol. 2017. doi: 10.1016/j.clinre.2017.04.004.