Independent Predictive Value of Elevated YKL-40 in Ischemic Stroke Prognosis: Findings from a Nationwide Stroke Registry.

INTRODUCTION: Elevated circulatory concentrations of YKL-40 have been reported in patients with ischemic stroke. This study further investigated the association of plasma YKL-40 concentrations at admission and short, long-term prognosis after ischemic stroke. METHODS: Based on a prospective, nationwide multicenter registry focusing consecutive patients of ischemic stroke and transient ischemic attack, plasma YKL-40 levels were detected by enzyme-linked immunosorbent assay at admission, and patients were stratified into percentile according to the plasma YKL-40 concentrations. The multivariate Cox or logistic regression model was used to investigate the association of YKL-40 concentration with death and functional outcomes at 3 months, 6 months, and 12 months after ischemic stroke, with potential confounders adjusted. RESULTS: A total of 8,006 first-ever ischemic stroke patients, with the age of 61.7 ± 11.5, were included in this study. The mortality of 0-33%, 34-66%, 67-90%, and 91-100% groups at 12 months follow-up was 0.9%, 2.2%, 4.4%, and 9.4%, respectively (p < 0.0001), and the modified Rankin Scale 3-6 ratio was 6.8%, 10.5%, 15.7%, and 24.0%, respectively (p < 0.0001). In the multivariate regression, after adjusting for potential confounders, 91-100% group had higher risk of death (hazard ratio 2.99, 95% confidence interval 1.75-5.11)and modified Rankin Scale 3-6 (odds ratio 1.42, 95% confidence interval 1.08-1.88) at 12 months since onset of ischemic stroke compared to the 0-33% group. CONCLUSIONS: The elevated YKL-40 at admission can potentially help predict death, functional prognosis after ischemic stroke, which may help further studies to explore the potential physiological and pathological mechanism including the effects of vulnerable plaque and collateral circulation.