Helicobacter pylori infection and small intestinal bacterial overgrowth: a systematic review and meta-analysis

Background There is a link between Helicobacter pylori (HP) infection and small intestinal bacterial overgrowth (SIBO) with nonspecific digestive symptoms.

Nonetheless, whether HP infection is associated with SIBO in adults remains unclear.

Based on a meta-analysis, we evaluated this relationship.

Results Observational studies relevant to our research were identified by searching PubMed, Embase, the Cochrane Library, and the Web of Science.

We evaluated between-study heterogeneity using the Cochrane Q test and estimated the I^2 statistic.

Random-effects models were used when significant heterogeneity was observed; otherwise, fixed-effects models were used.

Ten datasets from eight studies, including 874 patients, were involved in the meta-analysis.

It was shown that HP infection was related to a higher odds of SIBO (odds ratio [OR]: 1.82, 95% confidence interval: 1.29 to 2.58, p <  0.001) with mild heterogeneity ( p for Cochrane Q test = 0.11, I ^ 2  = 7%).

Subgroup analyses showed that HP infection was related to SIBO in young patients (mean age < 48 years, OR: 2.68, 95% CI: 1.67 to 4.28, p <  0.001; I ^ 2  = 15%) but not in older patients (mean age ≥ 48 years, OR: 1.15, 95% CI: 0.69 to 1.92, p <  0.60; I ^ 2  = 1%; p for subgroup difference = 0.02).

Subgroup analyses further indicated that the association was not significantly affected by the country of study, comorbidities, exposure to proton pump inhibitors, or methods of evaluating HP infection and SIBO.

Conclusions HP infection may be related to SIBO in adults, which supports the detection of SIBO in patients with digestive symptoms and HP infection.