An impact of ezetimibe on the carotid arterial wall elasticity in patients with hyper-LDL-cholesterolemia

Objective: The intima-media thickness (IMT) is a standard atherogenic parameter. However, the results from recent large-scale clinical trials indicate that the IMT may not be an exclusively reliable parameter. This is particularly evident when evaluating the impact of ezetimibe therapy on atheresclerosis. A pleiotropic review of various atherogenic parameters of ezetimibe is needed. This study aimed to evaluate the usefulness of IMT and other atherogenic parameters including elastic modulus of carotid arteries in patients receiving ezetimibe monotherapy for hyper-low-density-lipoprotein (LDL) cholesterolemia. Method: Nineteen patients with hypercholesterolemia were enrolled in the study. We examined the impact of six-month administration of ezetimibe 10 mg/day on various atherogenic parameters, including the pulse pressure, carotid IMT, brachial-ankle pulse wave velocity (baPWV), a carotid arterial wall elasticity modulus and percentage of brachial artery flow-mediated dilation (%FMD). Results: The six-month ezetimibe monotherapy tended to decrease the pulse pressure, carotid IMT, and baPWV values, but the changes were not significant. Ezetimibe therapy, however, significantly reduced both a carotid arterial wall elasticity modulus by 50% (190.2±50.9 kPa→120.3±31.2 kPa→94.5±27.1 kPa) (p<0.05) and LDL cholesterol (LDL-C) levels (155.7±34.0 mg/dL→126.1±31.5 mg/dL→127.5±26.6 mg/dL) (p<0.05) and significantly increased %FMD (5.4±7.3% →14.7±10.5% →8.9±6.4%) (p<0.05). These significant changes were maintained between the third and six months of the therapy. Conclusion: The study results show that ezetimibe administration significantly changes a carotid arterial wall elasticity modulus and increases %FMD as measured using transcutaneous ultrasound imaging, which suggests that ezetimibe may improve endothelial function.