No abstract

Psoriasis is an inflammatory skin disease. Despite the understanding of the disease pathogenesis, the link between diet-induced inflammation and the risk of psoriasis remains underexplored. Therefore, we have examined the capability of literature-derived Energy-adjusted Dietary Inflammatory Index (E-DII) as a predictive tool for inflammation, incidence, and severity of psoriasis (as indexed by The Psoriasis Area Severity Index (PASI)). We have conducted a case-control study consisting of 149 adults (n = 75 cases and n = 74 controls). The E-DII score was calculated based on the dietary intake that was evaluated by a validated 168 item quantity food-frequency questionnaire. The E-DII tertile cut-offs were categorized based on the following cut points: tertiles 1 ≤ −1.99; tertiles 2 = −2.00 - 0.60; tertile 3 ≥ 0.61. Logistic regression models were applied to estimate the multivariable odds ratio (OR) that was adjusted for confounders. Patients with higher pro-inflammatory E-DII had a 3.60-times increased risk of psoriasis relative to patients in tertiles 1 (E-DIIT3 vs E-DIIT1: OR = 3.64; 95% CI 1.51, 8.79, P = 0.005). The severity of disease as indexed by PASI remained associated with E-DII (E-DIIT3 vs E-DIIT1: OR = 3.64; 95% CI 1.74, 7.57, P = 0.015). For each unit increase in E-DII, the odds of disease severity increased by 3-times. Patients consuming a more pro-inflammatory diet were at greater risk of psoriasis. These patients also demonstrate increased disease severity relative to individuals consuming a more anti-inflammatory diet. • A pro-inflammatory diet is associated with higher psoriasis incidence • Subjects with higher DII scores, had higher inflammatory markers levels.