The aim of the present study was to quantify intima-media thickness (IMT) of the common carotid artery (CCA) in clinically asymptomatic members of familial combined hyperlipidemia (FCHL) families and to evaluate its association with lipids, apoproteins, blood pressure, surrogate markers of insulin resistance, fibrinogen and hs-CRP.
The group under study consisted of 82 individuals from 29 FCHL families (47 hyperlipidemic [HL] and 35 normolipidemic [NL]). They were compared with the age and sex adjusted control groups of healthy subjects (HL-c, n=20 and NL-c, n=20). IMT was measured by ultrasound at a far wall of both common carotid arteries.
Hyperlipidemic subjects had increased IMT compared with healthy controls (0.695+/-0.118 vs 0.599+/-0.074 mm), with an age and sex corrected difference of 86 mm (p<0.001). No difference in IMT was recorded in NL FCHL members in comparison with their healthy controls. In HL subjects, significantly positive univariate correlations were observed between IMT and age, total cholesterol, LDL-cholesterol, non-HDL-cholesterol, apolipoprotein B, SBP, DBP, BMI, waist, fasting glycemia, C-peptide and proinsulin, whereas in NL subjects IMT correlated only with age. Multivariate regression analysis in FCHL subjects (HL+NL) revealed that age (p<0.001), sex (p<0.001), non-HDL-cholesterol (p<0.01) and BMI (p<0.05) were significant and independent predictors of IMT.
The increase of IMT CCA in hyperlipidemic still clinically asymptomatic FCHL subjects corresponds to acceleration of the clinically ''silent'' atherosclerosis by about 8-14 years and is in agreement with their increased risk of atherosclerosis.