Inflammatory Potential of Diet is Associated with Increased Odds of Cataract in a Case-Control Study from Iran

Background: In previous studies, diet has been shown to be associated with cataract. However, no study to date has focused on the association between inflammatory potential of diet and cataract. OBJECTIVES: In this case-control study conducted in Iran, we examined the association of the dietary inflammatory index (DII®) and cataract. METHODS: This case-control study included 97 cataract cases and 198 healthy controls hospitalized for acute non-neoplastic diseases with the control group matched according to age (with a five-year interval) and sex with the case group. The DII was computed based on dietary intake assessed by a previously validated food frequency questionnaire. Multivariable logistic regression models were used to estimate odds ratios (ORs), with the DII analyzed as both continuous and as tertiles. Energy was adjusted using the residual method. RESULTS: Subjects with higher DII scores (i.e., with a more pro-inflammatory diet) had a higher odds of cataract, with the DII being used as both a continuous variable (ORcontinuous 1.51, 95% confidence interval, CI, 1.13 - 2.03; one unit increase corresponding to ≈18% of its range in the current study) and as tertiles (ORtertile3vs1 2.67, 95%CI 1.32 - 5.48, Ptrend = 0.002). CONCLUSIONS: These results indicate that a pro-inflammatory diet is associated with increased risk of cataract. Additional studies should be conducted to further explore this association.