Hiatal hernia and the risk of Barrett's esophagus

Background and Aim: Barrett's esophagus has been associated with the presence of hiatal hernia; however, to date no meta-analysis of the relationship has been performed. We aimed to conduct a systematic review and meta-analysis, providing a quantitative estimate of the increased risk of Barrett's esophagus associated with hiatal hernia. Methods: A search was conducted through four electronic databases (Medline, PubMed, Embase, and Current Contents Connect) to 4 April 2012, for observational studies of Barrett's esophagus patients. We calculated pooled odds ratios and 95% confidence intervals using a random effects model for the association of hiatal hernia with any length Barrett's esophagus, as well as with short segment Barrett's esophagus and long segment Barrett's esophagus. 33 studies comprising 4390 Barrett's esophagus patients were eligible for the meta-analysis. Results: Hiatal hernia was associated with an increased risk of Barrett's esophagus of any length (odds ratio 3.94; 95% confidence interval 3.02-5.13). Heterogeneity was present (I-2 = 82.03%, P < 0.001), and the Egger test for publication bias was significant (P = 0.0005). The short segment Barrett's esophagus subgroup analysis likewise showed an increased risk (odds ratio 2.87; 95% confidence interval 1.75-4.70). The strongest association was between hiatal hernia and long segment Barrett's esophagus (odds ratio 12.67; 95% confidence interval 8.33-19.25). The increased risk was present even after adjusting for reflux and body mass index. Conclusions: The presence of hiatal hernia was associated with an increased risk of Barrett's esophagus, even after adjusting for clinically significant confounders. The strongest association was found between hiatal hernia and long segment Barrett's esophagus.