Unraveling the impact of irritability on esophageal diseases: Insights from multivariable Mendelian randomization analysis

Background: Previous studies have suggested a potential association between irritability and the risk of various diseases. However, establishing a causal relationship has remained a significant challenge. To address this issue, we employed Mendelian randomization (MR), a sophisticated approach that leverages genotype data to emulate the conditions of randomized controlled trials. This method enables us to investigate the potential causal link between irritability and the susceptibility to esophageal diseases.

Methods: We conducted an extensive multivariable MR analysis using summary-level data from genome-wide association studies (GWAS) encompassing various esophageal diseases, including gastroesophageal reflux disease (GERD), esophageal cancer (EC), and Barrett's esophagus. Both univariable and multivariable MR analyses were performed to elucidate and confirm the causal association between genetically predicted irritability and the incidence of esophageal diseases.

Results: Based on our primary causal effects model utilizing MR analyses with the inverse-variance weighted (IVW) method, genetically predicted irritability was identified as a risk factor for GERD (OR = 2.413; 95 % CI: 1.678-3.470; P = 2.03E-06) and Barrett's esophagus (OR = 2.306; 95 % CI: 1.042-5.101; P = 0.039). However, irritability was not found to be associated with the risk of EC, even after adjusting for BMI, smoking initiation, and alcohol consumption.

Conclusion: The multivariable MR analysis performed in this study demonstrated a causal relationship between irritability and esophageal diseases. It is imperative to acknowledge the need for further large-scale prospective studies to validate these findings.