To Örebro University

PURPOSE: To examine and quantify the association between an inflammatory diet index and gastroesophageal reflux disease (GERD) utilizing extensive data from a large cohort.

METHODS: This study included eligible UK Biobank participants recruited between 2006 and 2010 who had no prior history of GERD and no missing data for key covariates. The primary outcome was incident GERD, identified using the "first occurrence" dataset. 27 eligible food/nutrient parameters derived from the 24-h recall questionnaires in the UK Biobank were included to calculate the energy-adjusted dietary inflammation index (E-DII) score. The E-DII score was employed as a continuous variable in restricted cubic spline regression (RCS) analysis. To facilitate analysis, participants were then categorized into four groups based on quartile values in the subsequent Cox regression analysis adjusting varying degrees of confounding factors.

RESULTS: After exclusion, 154,590 participants were included in the primary analysis. Over a mean 12.36-year follow-up, a total of 12, 041(7.79%) participants experienced GERD. The results of multivariable RCS showed that the risk of GERD had a slightly overall increased trend along with E-DII after adjusting the confounding factors. The cumulative incidence of GERD in the four groups was significantly different (P < 0.001) and participants in higher quartiles determined by E-DII had a higher GERD incidence. Results from both univariate and multivariate Cox regression consistently revealed the most pro-inflammatory E-DII group (i.e. the fourth quartile) had a significantly heightened risk of GERD compared to those in the first quartile (crude HR [95% CI] 1.118 [1.063-1.175]; fully adjusted HR [95% CI] 1.136 [1.079-1.196]). Subgroup analyses revealed variations across populations, while sensitivity analyses confirmed the robustness of primary findings.

CONCLUSIONS: The current study revealed that that adherence to a diet with high pro-inflammatory potential might be associated with higher GERD incidence and further randomized controlled trials are needed to provide more conclusive evidence.