Association of levels of interleukin 17 and T-helper 17 count with symptom severity and etiology of chronic heart failure: a case-control study

AIM: To assess the association between the levels of interleukin 17 (IL-17) and T-helper 17 count and symptom severity and etiology of chronic heart failure. METHODS: This single-center prospective case-control study, conducted from December 1, 2015 to January 1, 2017 in Tehran Heart Center, evaluated gene expression of IL-17, relative count of (CD4(+)IL17(+)) Th17 cells and CD4(+) helper T-cells in peripheral blood mononuclear cells of 42 patients with CHF and 42 matched controls. A multiple regression model assessed the predictors of peripheral IL-17 expression and Th17 count in patients with CHF. RESULTS: IL-17 expression was increased in patients with CHF, both at baseline and after stimulation. IL-17 and Th17 counts were higher in patients with advanced New York Heart Association (NYHA) functional class (class IV) than in controls and patients with class I. Th17 cell population expanded in patients with CHF, more prominently in patients with class IV than in controls and patients with class I, regardless of the ischemic or non-ischemic CHF origin. Multiple regression model showed that NYHA was the only meaningful predictor of IL-17 levels and Th17 count. CONCLUSION: We demonstrated the lymphocytic origin of IL-17 production in advanced CHF and the ability of disease severity to predict IL-17 levels. Oxford Centre for Evidence-based Medicine level of evidence: 3.