Abstract 12264: Coronary Artery Calcium Stratifies Risk Across Varying Levels of Dyslipidemia: The Multi-Ethnic Study of Atherosclerosis (MESA)
Background: The performance of the coronary artery calcium (CAC) score in risk assessment across the wide spectrum of dyslipidemia is uncertain, but relevant to the Adult Treatment Panel goal to match statin therapy to absolute risk. We hypothesized that the CAC score would show consistent performance in risk stratification across varying levels of dyslipidemia.
Methods: We examined the 5,534 MESA participants who were not on statin therapy or other medical treatments for dyslipidemia at baseline. Participants were classified as having 0, 1, 2, or 3 lipid abnormalities (LA), including LDL cholesterol ≥130 mg/dl, HDL cholesterol <40 mg/dl for men and <50 mg/dl for women, and triglycerides ≥150 mg/dl. We compared coronary heart disease (CHD) event rates and multivariable-adjusted hazard ratios after stratifying by LA and CAC.
Results: After a median follow-up of 7.6 years, 248 (4.5%) CHD events occurred. The figure shows that the CAC score consistently stratified CHD risk across varying levels of LA. In hierarchical multivariable-adjusted Cox regression models, the presence of CAC was strongly associated with CHD events in each LA group. Adjusting for age, gender, ethnicity, MESA site, and risk factors, the presence of CAC was associated with a hazard ratio for CHD of 3.1 (95% confidence interval, 1.4-6.8) in participants with 0 LA. The respective hazard ratios were 5.0 (2.7-9.4), 3.0 (1.4-6.5), and 4.3 (1.4-13.4) in those with 1, 2 and 3 LA. Similarly, the CAC score consistently stratified risk across categories of LDL cholesterol, non-HDL cholesterol, and the total to HDL cholesterol ratio; this was the case whether we used dataset-specific quartiles or guideline-defined categories.
Conclusion: In this prospective, population-based, multi-ethnic cohort of asymptomatic adults, the CAC score consistently stratified risk across varying levels of dyslipidemia, and therefore is a potentially robust clinical tool to promote matching of statin therapy to global risk.
- © 2012 by American Heart Association, Inc.