ABSTRACT
Background:
In observational studies, dietary intakes are associated with gastroesophageal reflux disease (GERD).
Aim:
To conduct a two-sample mendelian randomization (MR) analysis to determine whether those associations are causal.
Methods:
To explore the relationship between dietary intake and the risk of GERD, we extracted appropriate single nucleotide polymorphisms from genome-wide association study data on 24 dietary intakes. Three methods were adopted for data analysis: Inverse variance weighting, weighted median methods, and MR-Egger's method. The odds ratio (OR) and 95% confidence interval (CI) were used to evaluate the causal association between dietary intake and GERD.
Results:
Our univariate Mendelian randomization (UVMR) results showed significant evidence that pork intake (OR, 2.83; 95%CI: 1.76-4.55; P = 1.84 × 10-5), beer intake (OR, 2.70, 95%CI: 2.00-3.64; P = 6.54 × 10-11), non-oily fish intake (OR, 2.41; 95%CI: 1.49-3.91; P = 3.59 × 10-4) have a protective effect on GERD. In addition, dried fruit intake (OR, 0.37; 95%CI: 0.27-0.50; 6.27 × 10-11), red wine intake (OR, 0.34; 95%CI: 0.25-0.47; P = 1.90 × 10-11), cheese intake (OR, 0.46; 95%CI: 0.39-0.55; P =3.73 × 10-19), bread intake (OR, 0.72; 95%CI: 0.56-0.92; P = 0.0009) and cereal intake (OR, 0.45; 95%CI: 0.36-0.57; P = 2.07 × 10-11) were negatively associated with the risk of GERD. There was a suggestive association for genetically predicted coffee intake (OR per one SD increase, 1.22, 95%CI: 1.03-1.44; P = 0.019). Multivariate Mendelian randomization further confirmed that dried fruit intake, red wine intake, cheese intake, and cereal intake directly affected GERD. In contrast, the impact of pork intake, beer intake, non-oily fish intake, and bread intake on GERD was partly driven by the common risk factors for GERD. However, after adjusting for all four elements, there was no longer a suggestive association between coffee intake and GERD.
Conclusion:
This study provides MR evidence to support the causal relationship between a broad range of dietary intake and GERD, providing new insights for the treatment and prevention of GERD.
