Association between hiatal hernia and Barrett's esophagus: an updated meta-analysis with trial sequential analysis

Background: Barrett's esophagus (BE) is a precursor of esophageal adenocarcinoma. It is critical to recognize the risk factors associated with BE.Objectives: The present meta-analysis aims to systematically estimate the association of hiatal hernia with the risk of BE.Design: A meta-analysis with trial sequential analysis.Data sources and methods: The PubMed, EMBASE, and Cochrane Library databases were searched. The pooled odds ratios (ORs) and adjusted ORs (aORs) with their 95% confidence intervals (CIs) were calculated for the combined estimation of unadjusted data and data adjusted for confounders, respectively. Heterogeneity was quantified using the Cochrane Q test and I-2 statistics. Subgroup, meta-regression, and leave-one-out sensitivity analyses were employed to explore the sources of heterogeneity.Results: Forty-seven studies with 131,517 participants were included. Based on the unadjusted data from 47 studies, hiatal hernia was significantly associated with an increased risk of any length BE (OR = 3.91, 95% CI = 3.31-4.62, p < 0.001). The heterogeneity was significant (I-2 = 77%; p < 0.001) and the definition of controls (p = 0.014) might be a potential contributor to heterogeneity. Based on the adjusted data from 14 studies, this positive association remained (aOR = 3.26, 95% CI = 2.44-4.35, p < 0.001). The heterogeneity was also significant (I-2 = 65%; p < 0.001). Meta-analysis of seven studies demonstrated that hiatal hernia was significantly associated with an increased risk of long-segment BE (LSBE) (OR = 10.01, 95% CI = 4.16-24.06, p < 0.001). The heterogeneity was significant (I-2 = 78%; p < 0.001). Meta-analysis of seven studies also demonstrated that hiatal hernia was significantly associated with an increased risk of short-segment BE (OR = 2.76, 95% CI = 2.05-3.71, p < 0.001). The heterogeneity was not significant (I-2 = 30%; p = 0.201).Conclusion: Hiatal hernia should be a significant risk factor for BE, especially LSBE.