INTRODUCTION:
Coronary artery calcium (CAC) is a sensitive marker for the detection of subclinical coronary heart disease (CHD), and can be accurately quantified using cardiac computed tomography. Few studies have examined the relation between the metabolic syndrome (MetS), MetS risk factor burden, diabetes, and CAC.
HYPOTHESIS:
To examine the relation between MetS, as defined by the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III), MetS risk factor burden, diabetes and CAC.
METHODS:
We studied 356 consecutive, asymptomatic men and women aged 58 ± 11 years who underwent CAC testing, 116 had MetS, 61 had diabetes, and the remainder had neither. MetS was defined according to the NCEP ATP III guidelines with ≥ 3 risk factors. The prevalence and odds of CAC among these groups were determined by multivariable logistic regression analysis. Receiver operating characteristic curves were used to determine if MetS or diabetes added to 10-year CHD estimated by the Framingham risk score (FRS) in predicting CAC.
RESULTS:
The prevalence of CAC >0 for those with diabetes, MetS and neither condition was 73%, 69% and 60% respectively, while the prevalence of CAC ≥ 100 for the 3 groups was 64%, 43% and 24% respectively. Risk factor-adjusted odds for the presence of CAC ≥ 100 were 2.26 (95% CI 1 to 4.4, p=0.0001) among those with MetS and 3.46 (95% CI 1.6 to 7.4, p=0.0001) among those with diabetes, versus neither condition. ROC analysis for CAC ≥ 100 showed an area under the curve of 0.61 (95% CI 0.54 – 0.68) for FRS, 0.72 (95% CI 0.61– 0.83) for diabetes, 0.67 (95% CI 0.56 – 0.77) for the metabolic syndrome, 0.78 (95% CI 0.7– 0.85) when the MetS is added to the FRS (p<0.0001 compared to FRS alone), and 0.90 (95% CI 0.85– 0.95) when diabetes is added to the FRS (p<0.0001 compared to FRS alone). The CAC score showed a trend towards a progressive increase across the metabolic score ranging from 0 to 5 (p=0.0001).
CONCLUSIONS:
Those with MetS or diabetes have an increased likelihood of subclinical atherosclerosis (measured by CAC) compared to those with neither condition, and they also add to prediction of CAC over FRS, suggesting the importance of these factors in clinical assessment of CHD risk.
Coronary Artery Calcium Scores and Risk for Cardiovascular Events in Women Classified as “Low Risk” Based on Framingham Risk Score
