Inflammatory properties of diet mediate the effect of epilepsy on moderate to severe depression: Results from NHANES 2013–2018

Depression is a major public health problem, and epilepsy and a high-inflammatory diet are important causes of depression. We aimed to explore the level of dietary inflammation in epileptic patients and its relationship with moderate to severe depression (MSD).This cross-sectional study included 12,788 participants aged 20-80 years from the NHANES database from 2013 to 2018. Depressive symptoms were evaluated using the nine-item Patient Health Questionnaire (PHQ-9), and epilepsy was diagnosed based on the use of antiepileptic drugs within the previous 30 days. Dietary inflammatory index (DII) scores and energy-adjusted DII (E-DII) scores were calculated based on dietary recalls of the past 24 h, and average DII (ADII) and energy-adjusted ADII (E-ADII) were calculated based on two 24-hour dietary recalls.The DII, E-DII, and ADII scores and prevalence of MSD were significantly increased in epileptic patients compared with non-epilepsy subjects. The E-ADII score (P = 0.078) was weakly associated with comorbid MSD in patients with epilepsy. Mediation models showed that dietary inflammation scores mediated 2.31 % to 12.25 % of epilepsy-related MSD. In stratified analysis, an increased prevalence of MSD was present in the Quartile 2 subgroup based on DII and E-ADII scores and in the Quartile 3 subgroup of epileptic patients based on DII, E-DII, and ADII scores.Epileptics consume more proinflammatory foods and nutrients than control subjects. MSD in patients with epilepsy is associated with their high inflammatory diet. Suggesting an urgent need for rational dietary management in the epileptic population.