Abstract P333: Carotid Intima Media Echolucency is Related to Age, Female Sex, Systolic Blood Pressure, BMI and Smoking in Patients with Familial Hypercholesterolemia
Background: Atherosclerotic vascular disease can be assessed non-invasively with B-mode ultrasound. Echolucency is an ultrasound characteristic which is measured as the Gray Scale Median (GSM). Echolucent structures appear dark on ultrasound images; echogenic structures appear light. Echolucency of the carotid intima-media is thought to be a marker of the content of the vascular wall, where low values of GSM might reflect inflammation and/or high lipid content and high values of GSM reflect increased collagen and/or calcifications. In previous studies in asymptomatic individuals, echolucency of the carotid intima-media was associated with cardiovascular risk factors. Studies in high-risk populations are lacking. Aim: To assess the relation between cardiovascular risk factors and carotid intima media echolucency in patients with familial hypercholesterolemia. Methods: Baseline data were used from the RADIANCE 1 trial, a randomized controlled trial on the effects of atorvastatin and torcetrapib (a CETP-inhibitor) compared to atorvastatin alone in familial hypercholesterolemia. Echolucency of the common carotid artery intima media was measured as the mean GSM of the first baseline visit. Linear mixed effects models were used to assess the relation between each cardiovascular risk factor and mean GSM (adjusted for age, sex and carotid intima media thickness (CIMT), and in a multivariable model containing all risk factors). We studied systolic blood pressure (SBP), body mass index (BMI), high and low density lipoprotein (HDL and LDL), triglycerides (TGs), smoking, diabetes mellitus and C - reactive protein (CRP). Results: 875 patients were included in the current analysis. Mean age was 46 years (sd 13) and 50% was female. Mean GSM was 67 (sd 18). In age, sex and CIMT adjusted analyses, higher age (ß/sd: -5.71 (95% CI-6.82;-4.61)), female sex (β:-3.53 (95% CI -5.32;-1.73)), higher SBP (β/sd:-1.86 (95% CI -2.81;-0.91)), higher BMI (β/sd:-2.37 (95% CI -2.26;-1.29)) and higher levels of TGs (β/sd:-1.34 (95% CI -2.21;-0.47 were related to a lower GSM (i.e, more echolucency) and smoking (ß 2.91 (95% CI 0.52-5.29)) was related to a higher GSM. In the multivariable model, age (β/sd: -4.92 (95% CI -6.18;-3.65)), female sex (β: -4.35 (-6.41;-2.29), systolic blood pressure (β/sd: -1.32 (-2.38;-0.25) and BMI (β/sd: -1.82 (-2.90;-0.73)) were related to a lower GSM and smoking (β: 2.78 (0.39;5.18)) was related to a higher GSM. Conclusion: Several established risk factors were related to the echolucency of the common carotid intima media in patients with familial hypercholesterolemia.