Abstract 15365: Five Year Sustained Age and Gender Dependent Percentile Distribution of Coronary Artery Calcification as Estimate of Vascular Age - The Heinz Nixdorf Recall Study
Background: The amount coronary artery calcification (CAC) as a marker of atherosclerosis increases depending on age and gender and can be visualized as percentile distribution of CAC. The robustness of the distribution of CAC during follow-up of a general population cohort has not been examined. Objective: Analysis of changes in age and gender dependent percentile distribution of CAC during a five year follow-up period in a general population cohort based on electron beam computed tomography (EBCT).
Methods: In the study cohort of 1633 men and 1848 women (age 45 - 75 years), risk factors were determined and EBCT was performed at baseline and repeated after five years (t1, mean 5.1 ± 0.3 years). Mean regression analysis for association of log(CAC+1) with age for each gender was calculated and the transformed expected values of CAC were plotted as a function of age for the 50th, 75th, and 90th percentile at baseline and follow-up. Changes in the shape of age-dependent CAC-distribution over 5 years were regarded as estimated changes of vascular age.
Results: During follow-up, most risk factors were not significantly different (detailed data not shown). For women, the percentile distribution of CAC was nearly unchanged when baseline and 5-year follow-up values were compared (Fig. 1 A). In men, the values up to the 75th percentile of CAC distribution were similar for both time points, but for higher percentiles of CAC the 5-year curves demonstrated a small shift to the left and upwards, resulting in a shift of 2 years in estimated older vascular age (Fig. 1 B). For both genders, the threshold of CAC 100 and CAC 400 demonstrated a nearly unchanged detection rate.
Conclusion: The age and gender dependent distribution of CAC remained very robust over 5 years with the exception of the 90th percentile for men, emphasizing the high accuracy of the EBCT technique in repetitive studies, thus producing consistent estimates of vascular age.
- © 2013 by American Heart Association, Inc.