Abstract 11774: Coronary Artery Calcium and All-Cause Mortality

Abstract

Objectives: Coronary artery calcium (CAC) has been demonstrated as a non-invasive, low-cost means of assessing atherosclerotic burden and risk of major cardiovascular events in asymptomatic individuals. While it has been previously shown that CAC progression predicts all-cause mortality, we sought to further quantify this association by examining a large cohort of individuals over a follow-up period of between 1 to 22 years. Methods: We studied 3,260 persons aged 30 to 89 years who were referred by their primary care physician for CAC measurement, and had a follow-up scan at least 12 months from initial scan. CAC change was evaluated by absolute change between baseline and follow-up scan. Multivariate analyses using Cox proportional hazards models were used to compute hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between CAC progression and death after adjusting for age, gender, race and other risk factors. Participants were considered at risk from the date of exam 1 to the first occurrence of an event of death or lost to follow-up. The occurrence of death across the follow-up period was verified with the National Death Index. Results: The average time between scans was 4.7±3.2 years with an additional average of 9.1±4.0 years of follow-up time. The average age of the cohort was 58.1 ±10.5 years, 70% being male. A total of 164 deaths occurred. A clinical cut point of CAC progression of 100 units was significantly associated with mortality, hazard ratio 1.51 (95% CI 1.10 -2.13) P=0.017, while adjusting for age, gender, race, diabetes mellitus, hypertension, hyperlipidemia, smoking, baseline CAC and family history. Figure 1. Conclusions: CAC progression of greater than 100 units predicts all-cause mortality. This may add clinical value in encouraging close surveillance and aggressive treatment of individuals within this range.