increased il-17a in atrial fibrillation correlates with neutrophil to lymphocyte ratio

background: atrial fibrillation (af) is the most common cardiac arrhythmia and an independent risk factor for stroke among the elderly. a role for inflammation in the atrial remodeling as well as development and recurrence of af is known. objective: to compare il-17a between patients with different types of af and healthy individuals. methods: il-17a was measured in sera of 112 patients and 107 healthy age/sexmatched controls using elisa assay. in sera of 26 patients with elevated il-17a (>1 pg/ml), ccl5 and ccl18 levels were also measured. results: il-17a was significantly increased in patients with af compared to controls (1.28 ± 3.5 vs. 0.19 ± 0.64 pg/ml, p=0.001). there was no significant difference in the level of il-17a between different types of af. il-17a was significantly higher in patients with a history of coronary artery bypass graft compared to other patients (p=0.01). a significant positive correlation between il-17a and ccl18 concentration was found (p=0.001). an increase in the neutrophil/lymphocyte ratio (nlr) was observed in patients with elevated serum il-17a compared to other patients (p=0.006). male patients showed higher increase in nlr (p=0.007) which was accompanied by a decrease in ccl5 (p=0.000) and a marginal increase in ccl18 (p=0.085) compared to females. there was an increase in ccl5 levels in patients receiving acetylsalicylic acid (asa) therapy (p=0.046). conclusions: the increase in il-17a levels is related to the af pathology mediated by neutrophils and monocytes. the current study signifies the role of immune cells and cytokines in the pathology of af.