Association between Circulatory and Plaque Resistin Levels with Carotid Plaque Instability and Ischemic Stroke Events

Background: Carotid artery stenosis is one of the main causes of ischemic stroke. The risk of ischemic stroke increases with the degree of carotid stenosis and plaque vulnerability. The aim of this study was to investigate the association of circulating and plaque resistin levels with plaque vulnerability and ischemic stroke events in patients with moderate- to high-grade carotid artery stenosis. Methods: 40 patients with ischemic stroke events and 38 neurologically asymptomatic patients scheduled for carotid endarterectomy were recruited for this study. Fasting blood samples for laboratory analysis were collected preoperatively and serum resistin levels were measured by enzyme-linked immunosorbent assays. Carotid endarterectomy specimens were analyzed according to the gold-standard procedure of histological classification. Plaque resistin expression was determined by standard immunohistochemical procedure. Results: Serum resistin levels and resistin plaque expression were found to be significantly higher in subjects with unstable carotid plaque (P < .001) while significantly higher serum resistin levels were also present in patients with ischemic stroke events (P < .001). In univariate stepwise logistic regression analysis, higher serum resistin levels were significantly associated with plaque instability (OR 2.223, 95% CI 1.488-3.320, P < .0001) and ischemic stroke events (OR 1.237, 95% CI 1.079-1.420, P = .002). There was also a significant association between higher serum and plaque resistin expression (OR 1.663, 95% CI1.332-2.077, P < .0001). These associations remained significant in all models of multivariate logistic regression analysis. High serum and plaque resistin levels were also significantly associated with specific histological features of plaque instability. Conclusion: The results suggests that serum resistin levels may be used as a potential biomarker of plaque vulnerability and ischemic stroke events in patients with moderate- to high-grade carotid artery stenosis and highlight the possible relationship that plaque resistin expression has with histological features of plaque vulnerability.