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Race-specific data for the association between coronary artery calcification (CAC) and carotid intimal medial thickness (IMT) are limited. We sought to compare black-white specific associations of these two measures.We conducted a population-based study of 379 randomly selected men aged 40-49 years (84 black and 295 white) from Allegheny County, US (2004-2006). Agatston CAC score was evaluated by electron-beam tomography and carotid IMT was evaluated by ultrasonography.Compared to white men, black men had similar prevalence of CAC (p=0.56) and higher total carotid IMT (p0.001). In black and white men, CAC score had significant positive correlations with total carotid IMT (r=0.47 and r=0.24, respectively, p0.001 for both) as well as the IMT for the common carotid artery (CCA), internal carotid artery and carotid bulb. The associations of CAC with total and CCA IMT were significantly stronger in black (beta=0.07 and beta=0.05, respectively) than white men (beta=0.03 and beta=0.01, respectively) after adjustment for traditional coronary risk factors (p=0.046 and p=0.036, respectively).In black and white middle aged men, CAC score had significant positive correlations with total and segmental carotid IMT. CAC was more predictive of total and CCA IMT in black than white men independent of coronary risk factors.

The serum level of LOX-1 ligand containing ApoB (LAB) may reflect atherogenicity better than LDL cholesterol (LDLC), total LDL particles and usual measurement of oxidized LDL. The association between LAB and intima-media thickness (IMT) of carotid artery was investigated by ultrasound in US and Japan men.Participants were 297 US Caucasian and 310 Japanese men, aged 40-49 years without past history of cardiovascular disease. Serum LAB levels were measured by ELISAs with recombinant LOX-1 and monoclonal anti-apolipoprotein B antibody.Serum LAB levels [median (interquartile range), μg/L] were 1321 (936, 1730) in US Caucasians and 940 (688, 1259) in Japanese. For Caucasian men, average IMT was higher in higher LAB quartile, which was 0.653, 0.667, 0.688, and 0.702 mm, respectively (p for trend = 0.02). Linear regression analysis showed serum LAB was significantly associated with IMT after adjustment for LDLC or total LDL particles in addition to other traditional or novel risk factors for atherosclerosis such as C-reactive protein. However, there was no significant relationship between LAB and IMT in Japanese men.Serum LAB, a new candidate biomarker for residual risk, was associated with an increased carotid IMT in US Caucasian men independently of various risk factors; however, ethnic difference should be clarified in the future.

As part of an ancillary study to the Systolic Hypertension in the Elderly Program, carotid and lower extremity arterial disease (LEAD) were evaluated in 369 subjects, 186 with a systolic blood pressure (SBP)or = 160 mmHg, and 183 with SBP160 mmHg. Both groups had a diastolic blood pressure (DBP)90 mmHg. Internal carotid stenosis was identified by Doppler and LEAD was assessed using the ankle to arm systolic blood pressure ratio, commonly called the ankle/arm index (AAI). Lp(a) values were obtained from frozen sera and valuesor = 20 mg/dl were considered elevated. Rates of carotid stenosis were 24% among those with an Lp(a)or = 20 mg/dl and 14% among those with an Lp(a) level20 mg/dl (P = 0.020). The relationship between Lp(a) and LEAD was even stronger. Those with an Lp(a)or = 20 mg/dl had a 36% prevalence of a low AAI vs 14% among those with a Lp(a) level20 mg/dl (P0.001). Lp(a) values were also associated with the severity of LEAD. Controlling for other risk factors did not reduce the association between either LEAD or carotid stenosis and an Lp(a)or = 20 mg/dl. Thus, Lp(a) appears to be independently associated with peripheral atherosclerosis in older adults, both men and women. The relationship is particularly strong for atherosclerotic disease of the lower extremities.

The distributions of plasma total cholesterol, apolipoproteins A-I and B and lipoprotein(a) levels as well as genetic typings of apolipoprotein(a) and apolipoprotein E were determined in a randomly selected sample of American Black women (mean age 22.2 +/- 6.5 years) . Mean plasma levels of cholesterol, apolipoprotein A-I, apolipoprotein B and lipoprotein(a) were 184.5 +/- 3.0 mg/dl, 138.0 +/- 3.1 mg/dl, 79.5 +/- 1.8 mg/dl and 24.5 +/- 1.5 mg/dl, respectively. Plasma lipoprotein (a) levels correlated significantly with apolipoprotein B and cholesterol. The contribution of apolipoprotein (a) and apolipoprotein E polymorphisms in affecting these quantitative traits was evaluated. The apolipoprotein(a) locus was extremely polymorphic with 27 alleles, while the 3 common alleles were observed in the apolipoprotein E gene. The frequencies of the APOE*2, APOE* and APOE*4 alleles were 0.094, 0.674 and 0.232, respectively. An inverse relationship was observed between the size of apolipoprotein(a) isoforms and lipoprotein(a) levels (r = 0.37; P = 0.0001). The apolipoprotein E polymorphism revealed a significant genotypic effect on apolipoprotein B (P = 0.0008) and cholesterol (P= 0.005) levels; these concentrations were lower in the APOE 2-3 genotype and higher in the 3-4 and 4-4 genotypes compared with the common 3-3 genotype. The apolipoprotein E polymorphism explained 15.8% and 6.3% of the phenotypic variance in apolipoprotein B and cholesterol levels, respectively. This study demonstrates that genetics play an important role in determining quantitative risk factors for coronary heart disease among American Black women.