Background: Growing evidence shows that non-high-density lipoprotein cholesterol (Non-HDL-C) is a strong and independent predictor of cardiovascular disease (CVD). Few studies have assessed the association between traditional lipid measures and subclinical end points. In this study we analyzed the association of Non-HDL-C, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG) with coronary artery calcium (CAC), a marker of subclinical atherosclerosis.
Methods: The study population consisted of 1611 consecutive asymptomatic individuals (67% men, mean age: 53+/-10 years) referred to a single electron beam tomography (EBT) facility for CAC screening. Multivariate logistic regression was used to test the association between increasing quartiles of lipid levels and presence of CAC score (CACS)>0 and CACS>or=100, with the lowest levels (first quartile) of lipid values as reference.
Results: Overall CACS of 0, 1-99, 100-399 and >or=400, were observed in 35%, 44%, 12% and 9% of the study subjects, respectively. The prevalence of CAC increased significantly across increasing quartiles of LDL-C, TG and Non-HDL-C (all p<0.0001), whereas CACS was significantly lower across increasing quartiles of HDL-C (p<0.001). In a multivariate model controlling for age, gender, race, cigarette smoking, hypertension, family history of coronary artery disease and obesity, there was a significant increase in the prevalence of CAC with increasing values of each lipid variable. In a multivariate model simultaneously controlling for increasing quartiles of the remaining lipid variables, only the association of Non-HDL-C with CACS>0 remained statistically significant (p=0.002). Similar results were observed with CACS>or=100 (p=0.038).
Conclusion: In this study Non-HDL-C was more strongly associated with subclinical atherosclerosis than all other conventional lipid values. These data suggests that Non-HDL-C may be an important treatment target in primary prevention.