Predictive Value of Dietary Inflammatory Index for Recurrence of Plaque Psoriasis—A Retrospective Study

<b>Aims/Background</b> Determining the predictive value of dietary inflammatory index on the recurrence of plaque psoriasis vulgaris is an emerging research area. This study aims to investigate the predictive value of the dietary inflammatory index (DII) for the recurrence of plaque psoriasis. <b>Methods</b> A retrospective study was conducted on 200 patients with plaque psoriasis who were treated at the China-Japan Friendship Hospital from October 2022 to December 2023. Patients were divided into the recurrence group (n = 95) and the non-recurrence group (n = 105) based on whether they had experienced a recurrence during follow-up. Univariate and multivariate logistic regression analyses were performed to determine the influencing factors of plaque psoriasis recurrence. The receiver operating characteristic (ROC) curve was used to evaluate the predictive value of the DII for plaque psoriasis recurrence. <b>Results</b> Comparisons of age, gender, Drinking, duration of illness, family history, season of onset, and history of skin allergies showed no statistically significant differences between the recurrence group and non-recurrence group (<i>p</i> > 0.05). However, comparisons of sleep inadequacy, anxiety, smoking, infections, and DII showed statistically significant differences between the recurrence group and non-recurrence group (<i>p</i> < 0.05). The results of the multivariate logistic regression analysis indicated that sleep inadequacy, anxiety, smoking, infections, and DII were independent influencing factors for the recurrence of plaque psoriasis (<i>p</i> < 0.05). The ROC analysis results showed that the predicted area under the curve of DII in predicting recurrence of plaque psoriasis vulgaris was 0.815, and the standard error was 0.031 (95% confidence interval (CI): 0.754-0.877, <i>p</i> < 0.001) with a Youden's index of 0.60, sensitivity of 74.7%, and specificity of 84.8%. DII has the highest predictive value. <b>Conclusion</b> Characterized by high specificity and sensitivity from the ROC curve analysis, the DII exhibits a high predictive value for plaque psoriasis recurrence.