Dietary Inflammatory Index and Risk of Multiple Sclerosis in a Case-Control Study from Iran

Abstract

Background: Diet and inflammation have been suggested to be important risk factors for multiple sclerosis (MS). Objectives: In this study, we examined the ability of the dietary inflammatory index (DII) to predict MS in a case-control study conducted in Iran. Methods: This study included 68 MS cases and 140 controls hospitalized for acute non-neoplastic diseases. The DII was computed based on dietary intake assessed by a previously validated food frequency questionnaire. Logistic regression models were used to estimate ORs adjusted for age, energy, sex, body mass index, season of birth, rubella history, history of routine exercise before MS, smoking and history of consumption of cow's milk in the first 2 years of life. Results: Subjects with higher DII scores (i.e., with a more pro-inflammatory diet) had a higher risk of MS, with the DII being used both as a continuous variable (OR_continuous 1.66; 95% CI 1.19-2.31; 1 unit increase corresponding to ≈15% of its range in the current study) and a categorical variable (OR_{DII (>1.43 vs.}_≤_1.43) 2.68; 95% CI 1.15-6.26). Conclusions: These results indicate that a pro-inflammatory diet is associated with increased risk of MS.