Background & Aims
Barrett’s esophagus (BE) is a pre-malignant condition to esophageal adenocarcinoma. Due to conflicting evidence, it is currently not clear whether cigarette smoking increases the risk of developing BE, and no meta-analysis has been performed on the topic. We conducted a systematic review and meta-analysis, providing a quantitative estimate of the increased risk of BE associated with cigarette smoking, to help clarify whether a relationship exists between smoking and BE.
Four electronic databases (Medline, PubMed, Embase, and Current Contents Connect) were searched to April 18, 2012, for observational studies of BE patients. We calculated pooled odds ratios (ORs) and 95% confidence intervals (CIs) using a random effects model for the association of smoking with BE. BE patients were compared with non-gastroesophageal reflux disease (GERD) controls as well as with population-based and GERD controls.
Thirty-nine studies comprising 7069 BE patients were included in the meta-analysis. Having ever smoked was associated with an increased risk of BE compared with non-GERD controls (OR 1.44; 95% CI 1.20-1.74), population-based controls (OR 1.42; 95% CI 1.15-1.76), but not GERD controls (OR 1.18; 95% CI 0.75-1.86). The meta-analyses of the studies reporting the lowest and highest number of pack-years smoked showed an increased risk of BE (OR 1.41; 95% CI 1.22-1.63) and (OR 1.53; 95% CI 1.27-1.84), respectively.
Cigarette smoking was associated with an increased risk of BE. Being an ever-smoker was associated with an increased risk of BE in all control groups. A greater number of pack-years smoked was associated with a greater risk of BE.