The causal relationship between chronic obstructive pulmonary disease and Barrett’s esophagitis: A two-sample Mendelian randomization study

The aim of the study was to investigate the causal relationship between chronic obstructive pulmonary disease (COPD) and Barrett's esophagus (BE) using two-sample Mendelian randomization (MR). We obtained summary-level genome-wide association study data on COPD and BE from the integrative epidemiology unit of the open genome-wide association study project, and selected significant single nucleotide polymorphisms as instrumental variables. Various MR analysis methods were employed to assess the causal effect of COPD on BE and vice versa. The methods selected include inverse variance weighted (IVW) analysis, weighted median analysis, and MR-Egger analysis. The MR resonance imaging revealed a bidirectional causal relationship between COPD and BE. IVW analysis indicated that COPD increased the risk of BE (odds ratio [OR]: 1.24, 95% confidence interval [CI]: 1.12-1.34, P = 3.0 × 10⁻⁵), which was supported using the weighted median method (OR = 1.16, 95% CI: 1.01-1.33, P = .04). These findings were robust in the pleiotropy analysis (MR-Egger intercept = 0.02). Conversely, BE also increases the risk of COPD (IVW OR: 1.080, 95% CI: 1.03-1.13, P = .001), with supporting evidence from the weighted median method (OR = 1.09, 95% CI = 1.03-1.15, P = .005). These findings were robust in the pleiotropy analysis (MR-Egger intercept = 0.001). Our study findings reveal a bidirectional causal link between COPD and BE, highlighting the need for mechanistic research to elucidate the underlying pathways. These insights can improve our knowledge of novel screening and prevention strategies, emphasizing the importance of targeted healthcare measures.