Relation of Plasma Tissue Kallikrein Levels to Presence and Severity of Coronary Artery Disease in a Chinese Population

OBJECTIVES: Tissue kallikrein (TK) has been shown to provide cardiovascular and cerebrovascular protective effects in animal models. The aim of this study was to investigate the relationship of plasma TK levels with the presence and severity of coronary artery disease (CAD) in the Chinese. METHODS: The study involved 898 consecutive CAD patients and 905 ethnically and geographically matched controls. CAD was angiographically confirmed in all the patients, and the severity of CAD was expressed by the number of affected vessel and coronary artery stenosis scores. Plasma TK levels were measured using an enzyme-linked immunosorbent assay. RESULTS: Plasma TK levels were significantly higher in CAD patients than controls (0.347±.082 vs. 0.256±0.087 mg/L, P<0.001), and elevated plasma TK levels were directly associated with a higher risk of CAD (OR = 3.49, 95% CI 2.90-4.19). One-way ANOVA and multivariable stepwise linear regression analysis demonstrated that TK levels were negatively associated with the severity of CAD according to vessel scores (P<0.001) and stenosis scores (r = -0.211, p<0.001). CONCLUSIONS: Our findings suggest that higher levels of TK in plasma are associated with the presence of CAD and are a predictor of mild coronary arteriosclerosis.