Relation of Coronary Artery Calcium to Flow-Mediated Dilation and C-Reactive Protein Levels in Asymptomatic Patients With Heterozygous Familial Hypercholesterolemia

The extent of coronary artery calcium (CAC) is correlated with coronary artery disease prognosis. However, the relation of CAC to endothelial function and high-sensitivity C-reactive protein (hs-CRP) in patients with asymptomatic heterozygous familial hypercholesterolemia (FH) requires clarification. The study aim was to investigate the relations among CAC, endothelial function, and hs-CRP in patients with asymptomatic heterozygous FH. Thirty-two patients with asymptomatic heterozygous FH (mean age 42 years) and 34 healthy control subjects (mean age 36 years) were enrolled. We measured CAC by electron-beam computed tomography and endothelial function by flow-mediated dilation of the brachial artery. A higher percentage of patients with FH had a positive CAC score compared with the control group. Comparing the FH group with detectable CAC (CAC score >0) and undetectable CAC (CAC score of 0), we found higher hs-CRP levels (0.29 ± 0.23 vs 0.07 ± 0.08 mg/dl, p = 0.001) and reduced flow-mediated dilation (0.04 ± 0.03 vs 0.08 ± 0.03, p = 0.005) in the detectable CAC group. Multivariate analysis showed an independent correlation of hs-CRP with detectable CAC (relative risk 5.034, 95% confidence interval 1.525 to 16.613, p = 0.04). In conclusion, FH subjects with positive CAC scores have decreased flow-mediated dilation and increased hs-CRP levels. Furthermore, hs-CRP level is the only independent predictor of the presence of CAC.