Causal analysis between gastroesophageal reflux disease and chronic rhinosinusitis

Background Gastroesophageal reflux disease (GERD) and chronic rhinosinusitis (CRS) have been shown to be potentially closely related, but the relationship between these conditions, particularly the possibility of a causal link, is not fully understood. This study used Mendelian randomization (MR) to assess the causal relationship between these two disorders.Methods We extracted genome-wide association study data sets for GERD and CRS from publicly available gene summaries, and used MR to conduct a causal inference analysis. The main robustness test used in this study included MR-Egger regression, a leave-one-out sensitivity test, and multivariate MR (MVMR).Results GERD increased the risk of developing CRS by 36%, based on the inverse-variance weighted method, a statistically significant association (odds ratio [OR] 1.360, 95% confidence interval [CI] 1.179-1.568, P < 0.001). Other MR assessment methods, such as weighted median, simple mode, and weighted mode, similarly observed a significant increase in the risk of CRS occurrence (OR 1.434, 95% CI 1.186-1.734, P < 0.001; OR 1.927, 95% CI 1.166-3.184, P = 0.013; and OR 1.910, 95% CI 1.222-2.983, P = 0.006, respectively). No significant bias was found in the heterogeneity or pleiotropy tests (P = 0.071 and P = 0.700, respectively). Even after excluding possible mediators using MVMR, GERD appeared to significantly increase the risk of developing CRS (OR 1.013, 95% CI 1.008-1.023, P = 0.002).Conclusions This study provides new, significant evidence that GERD is genetically associated with a higher incidence rate of CRS. However, further research is needed to elucidate the potential underlying biological mechanisms of this relationship.