The Association of Dietary Inflammatory Index with the Risk of Peptic Ulcer: A Case-Control Study

Peptic ulcer disease (PUD) is a gastrointestinal ulcer caused by gastric acid. Aging, smoking and alcohol, stressful life, and family history are directly related to PUD. Oxidative stress and inflammation are the most important mechanisms involved in PUD. The aim of this study is to evaluate the association of dietary inflammatory index (DII) with the risk of PUD.

In this case-control study, data from 100 newly diagnosed peptic ulcer patients and 150 healthy individuals were analyzed. DII was assessed based on dietary intake data collected through a 174-item validated food frequency questionnaire (FFQ). To calculate DII, 36 nutrients and food components were used after adjusting the energy intake. Adjusted odds ratios (OR) and 95% confidence intervals (CI) regarding the association between DII and PUD risk were estimated by logistic regression.

The mean DII score in patients (0.43±1.88) was significantly higher than the mean DII in healthy individuals (-2.88±2.00) (P=0.005), i.e. patients had received more inflammatory diet. In the crude model of PUD, odds increased significantly in the third and fourth quartiles of DII score compared to the lowest quartile (OR of third quartile vs first quartile: 2.65, 95% CI:1.27-5.52, respectively; and OR of fourth quartile vs first quartile: 2.33, 95% CI:1.12-4.85, respectively; P- trend=0.001). After checking multiple potential confounders, OR in third and fourth quartiles remained high and there was no change in the results.

These findings suggest that more pro-inflammatory diets, indicated by higher DII scores, may increase the risk of PUD. Therefore, anti-inflammatory diet may play a protective role against PUD.