High serum level of interleukin-6 is linked with dyslipidemia in oral lichen planus

Oral lichen planus (OLP) is a complex chronic inflammatory disorder in which autocytotoxic CD8⁺ T cells, locally present in the affected tissue, induce basal keratinocyte apoptosis, through the release of several cytokines, such as interleukin-6 (IL-6). IL-6 is a proinflammatory cytokine that is related to alterations in lipid metabolism in psoriasis patients. Impaired lipid metabolism together with high serum levels of triglycerides have been found in association with OLP. However, the correlation between serum levels of IL-6 and dyslipidemia has not yet been studied in this disorder. The present study aimed to demonstrate the association between OLP, systemic inflammation through increased release of inflammation mediators such as IL-6 and alteration of lipid metabolism, in order to support the concept of OLP as a marker of systemic inflammation and a potential risk factor of cardiovascular morbidities. For this purpose, we designed a case-control study using a cohort of 18 patients with different clinical forms of OLP compared with 18 control group patients with other oral conditions, to identify a potential correlation between serum levels of IL-6 and serum lipid levels. High plasma serum levels of IL-6 were found to be correlated with cholesterol, high density lipoprotein cholesterol and triglyceride serum levels in the patients with OLP. There was a significant association between erosive and atrophic clinical forms of OLP and the pathological serum values of IL-6 and triglycerides, respectively, making these two parameters good predictive factors of the clinical form of OLP. Further studies of other biomarkers of systemic inflammation using larger cohorts of OLP patients are necessary in order to consider LP as a marker of systemic inflammation and to support the screening of these patients for lipid metabolism changes and treatment with specific antagonists in order to prevent cardiovascular events.