Association of serum YKL-40 levels with the presence and severity of coronary artery disease in patients with obstructive sleep apnea syndrome.

PURPOSE Current evidence supports a robust association between obstructive sleep apnea syndrome (OSAS) and the risk of coronary artery disease (CAD). YKL-40, a 40 kDa heparin- and chitin-binding glycoprotein, is found to be associated with the presence of CAD. This study aims to examine the association of serum levels of YKL-40 with the presence and severity of CAD in patients with OSAS. METHODS A total of 246 patients with OSAS who underwent coronary angiography for the evaluation of CAD (134 patients with CAD and 112 patients without CAD) were enrolled in this study. The severity of CAD was assessed using the coronary atherosclerosis index (CAI). Serum levels of YKL-40 were determined using enzyme-linked immunosorbent assay. RESULTS Serum YKL-40 levels were significantly higher in OSAS patients with CAD compared with those without CAD. Multivariable logistic regression analysis revealed that serum YKL-40 levels were an independent determinant of the presence of CAD in patients with OSAS. In addition, Spearman correlation analysis showed that serum YKL-40 levels were positively correlated with CAI in OSAS patients with CAD. Patients with statin treatment showed significantly lower levels of serum YKL-40 compared with those without. CONCLUSIONS Elevated levels of serum YKL-40 are associated with the presence and severity of CAD in patients with OSAS.