Conventional versus image-based cardiovascular risk assessment in Korean adults

The aim of this study is to evaluate the difference between risk stratifications according to the National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III) guideline and the coronary artery calcium score (CACS) in a Korean population at an intermediate risk.

A total of 7988 nondiabetic individuals underwent coronary computed tomography to measure coronary artery calcium. The discordantly higher risk group (DHRG) was defined as individuals whose CACS risk category was discordantly higher than their risk category according to the NCEP-ATP III guideline.

Among all individuals at a low to moderate risk according to NCEP-ATP III, 9.4% were reclassified to the DHRG by CACS. In the multivariate regression analysis, age [odds ratio, 95% confidence interval (CI): 1.140 (1.123-1.158)], female sex [0.312 (0.208-0.469)], alcohol consumption [1.383 (1.142-1.676)], uric acid [1.079 (1.005-1.158)], hemoglobin A1c [1.716 (1.225-2.404)], fasting insulin [1.275 (1.056-1.539)], and systolic blood pressure [1.008 (1.001-1.016)] were associated independently with the DHRG. In a receiver-operating characteristic analysis, age had the largest area under the curve (AUC) compared with all of the aforementioned significant variables [AUC (95% CI): 0.724 (0.705-0.743)] for the DHRG. For every 5 years over 35 years of age, the risk of being in the DHRG increases by 1.95.

This study indicates that the NCEP-ATP III guideline underestimates cardiovascular risk in about 10% of asymptomatic nondiabetic Korean individuals in the lower to moderate risk group, and the discrepancy in risk stratification between NCEP-ATP III and CACS is particularly prominent in older individuals. This suggests that an image-based risk assessment such as a coronary calcium scan should be considered for more accurate risk stratification.