Association between plasma proprotein convertase subtisilin/kexin type 9 concentration and coronary artery calcification

Background Plasma proprotein convertase subtilisin/kexin type 9 (PCSK9) has been reported to be related to several risk factors and diseases such as inflammatory markers and coronary artery disease. The aim of present study was to investigate whether plasma PCSK9 concentration was associated with coronary artery calcification. Methods A total of 403 consecutive untreated patients with angina-like chest pain, who received electron beam computed tomography, were enrolled and a coronary artery calcification score (CACS) was also measured. The baseline clinical characteristics were collected and blood sample was taken after 12-h fasting. The plasma PCSK9 concentrations were determined by ELISA in all patients, and the relationship between plasma PCSK9 concentrations and CACS was investigated. Results Patients with coronary artery calcification (CACS>0) had significant higher plasma PCSK9 concentrations compared with those (CACS=0) without coronary artery calcification (258.5869.53ng/mL vs. 202.53 +/- 52.17ng/mL, P<0.001). Patients with highest PCSK9 concentrations had the highest CACS. Multivariable linear regression analysis suggested that PCSK9 was independently associated with coronary artery calcification (P=0.002) after adjusting for traditional cardiovascular risk factors. Furthermore, the area under the curve for the plasma PCSK9 concentration in predicting coronary artery calcification was 0.736 (95% CI: 0.687-0.785, P<0.001), with a sensitivity of 66% and specificity of 70%. Conclusion A positive association between plasma PCSK9 concentration and coronary artery calcification in untreated patients with angina-like chest pain was observed in our study, suggesting that further investigation may be needed in order to confirm our primary findings and explore the clinical implications.