Carotid intimal-medial thickness and stiffness are not affected by hypercholesterolemia in uncomplicated essential hypertension

The combined effects of hypertension and hypercholesterolemia on carotid an atomy and stiffness were studied in 62 normotensives, 141 uncomplicated ess ential hypertensives with a total cholesterol level <240 mg/dL, and 60 esse ntial hypertensives with a total cholesterol level greater than or equal to 240 mg/dL. Carotid ultrasonography was performed to evaluate intimal-media l thickness (IMT), relative wall thickness, and the presence of plaque. Car otid pressure waveforms were recorded by applanation tonometry to measure c arotid stiffness (beta) and pressure wave reflection (ie, augmentation inde x). After adjusting for age, body mass index, and smoking habit by analysis of covariance, no significant differences were found between normocholeste rolemic hypertensives and hypercholesterolemic hypertensives in terms of IM T (0.79+/-0.19 versus 0.81+/-0.19 mm), relative wall thickness (0.27+/-0.07 versus 0.28+/-0.07), carotid stiffness (6.1+/-3.2 versus 5.6+/-2.7), augme ntation index (18.7+/-12.9% versus 17.3+/-12.8%), and prevalence of plaque (30.8% versus 30.7%). In the whole population, carotid IMT was significantl y related to age (r=0.43), systolic (r=0.35) and diastolic (r=0.35) blood p ressures, body surface area (r=0.22), and cholesterol levels (r=0.22) (all P<0.05). Carotid stiffness was significantly related to age, blood pressure , body mass index, and body surface area but not to cholesterol levels. In multivariate analyses, age, body surface area, and systolic blood pressure, but not cholesterol, smoking habit, or sex, were independent correlates of IMT (multiple R=0.54, P<0.0001), whereas carotid stiffness was independent ly associated with age, body surface area, and sex (R=0.38, P<0.0001), In c onclusion, hypertension is a patent stimulus of vascular hypertrophy. The s uperimposition of hypercholesterolemia does not substantially augment these changes or further increase arterial stiffness in uncomplicated hypertensi ve subjects.