Association of serum proprotein convertase subtilisin/kexin type 9 with carotid intima media thickness in hypertensive subjects

Objective The clinical significance of the measurement of serum PCSK9 (proprotein subtilisin kexin type 9) is not well defined. This study investigated the association between serum PCSK9 levels and atherosclerosis assessed by carotid intima media thickness (IMT) in hypertensive patients. Methods A total of 126 hypertensive patients over the age of 45 were enrolled. The maximum carotid IMT (max-IMT) and the mean carotid IMT (mean-IMT) were measured at the time of enrollment. Clinical and laboratory parameters including serum PCSK9 were analyzed. Results Patients were divided into tertiles based on serum PCSK9 levels. After adjusting for age, sex, total cholesterol, HDL-cholesterol and triglyceride, max-IMT was significantly increased in the highest tertile of serum PCSK9 (0.969 ± 0.033 vs 0.959 ± 0.033 vs 1.077 ± 0.033 mm, respectively; P = 0.026). Mean-IMT showed a tendency to increase across the tertile groups (0.773 ± 0.025 vs 0.790 ± 0.026 vs 0.856 ± 0.025 mm, respectively; P = 0.059). Multivariate regression analysis revealed that serum PCSK9 was independently associated with carotid IMT (max-IMT: β = 0.212, P = 0.016; mean-IMT: β = 0.184, P = 0.04). Conclusion The present study is the first to report the association between serum PCSK9 levels and carotid IMT in hypertensive patients. These results suggest that serum PCSK9 may have a certain role in early pathogenesis of atherosclerosis.