Abstract
We aimed to investigate the association with the Dietary Inflammatory Index (DII™) on the risk of gastric cancer and whether histological type modifies this association. From March 2011 to December 2014, 388 cases and 776 controls were enrolled at the National Cancer Center. Utilizing a food frequency questionnaire, thirty-five food components were used to score the DII. The tertile distribution of DII for controls was as follows: T1: <0.96, T2: 0.96-2.97, and T3: ≥2.97. To investigate the association between DII and the gastric cancer risk, multivariable logistic models were constructed. In subgroup analyses, histological types including intestinal and diffuse types were examined. As the DII increased, gastric cancer risk increased (p-value for trend =0.007). Participants in the highest DII tertile had a greater gastric cancer risk compared to those in the lowest tertile [Odds Ratio (OR) =1.63, 95% Confidence Interval (CI) 1.15-2.29]. Stratification by sex revealed that men who were in the highest DII tertile showed a greater risk of intestinal type (OR=2.03, 95% CI 1.09-3.77). Participants positive for H. pylori infection had higher risk of intestinal type (OR=2.16, 95% CI 1.21-3.87). In this case-control study, we found a significantly positive association with a pro-inflammatory diet on gastric cancer risk, after adjusting for covariates. Future studies are suggested to prospectively examine the effect of a pro-inflammatory diet on gastric cancer risk.