RESUMO
Objective: To investigate the relationship between plasma level of pro-protein convertase subtilisin kexin type9 (PCSK9) and coronary artery calcification (CAC). Methods: A total of 380 consecutive chest pain patients without lipid-lowering therapy were enrolled. All patients received CT scan and coronary artery calcification (CAC) score measurement and were divided into 2 groups: CAC group, n=156 patients with CAC score>0 and Non-CAC group, n=224 patients with CAC score=0. CAC group was further classified in 3 subgroups as CAC score (1-100) subgroup, n=53, CAC score (101-400) subgroup, n=64 and CAC score>400 subgroup, n=39. Clinical data was collected, plasma levels of PCSK9 were measured in all patients and the relationship between PCSK9 and CAC score was investigated. Results: Plasma PCSK9 level in CAC group was higher than Non-CAC group (260.23±69.34) ng/ml vs (205.46±53.21) ng/ml, P<0.001; alone with CAC score increasing, PCSK9 level was elevating accordingly as in CAC score (1-100) subgroup, CAC score (101-400) subgroup and CAC score>400 subgroup, PCSK9 levels were (247.38±72.68) ng/ml, (264.87±57.63) ng/ml and (295.33±69.06) ng/ml respectively, all P<0.05. With adjusted traditional cardiovascular risk factors, multivariate regression analysis confirmed that plasma PCSK9 level was independently related to CAC score (β=0.584, P=0.002). In addition, the optimal cut-off value for PCSK9 predicting CAC was 228.58 ng/ml with sensitivity at 67% and specificity at 71%. Conclusion: Plasma PCSK9 level was related to CAC in chest pain patients without lipid-lowering therapy.