Objective: To determine which of the standard cardiovascular risk factors have the strongest associations with prevalent coronary artery calcification (CAC).
Study design and setting: A cross-sectional study of 6086 consecutive subjects who underwent electron beam computed tomography for CAC at a private, university-affiliated disease prevention center in San Diego, CA.
Results: The correlation between age and coronary calcium score in men (r=0.463) was twice that of the next highest correlation (0.218) for percent body fat. A similar relationship was found for women (0.413 vs. 0.238). Calcium scores increased incrementally by age category in both men and women. This pattern of increase was not present for LDL cholesterol. Men and women over the age of 74 had highly elevated risks for the presence of any calcified coronary atherosclerosis compared to those under the age of 45 (OR [95% CI]: 11.08 [6.186-19.859] and 11.81 [6.718-20.746], respectively). Addition of the other traditional cardiovascular risk factors did not significantly increase the discriminatory power beyond that provided by age on ROC analysis.
Conclusion: Age and gender are significant independent clinical correlates of coronary calcium beyond that provided by the other risk factors. These results support the hypothesis that age is the predominant risk factor for coronary calcification.