Current guidelines recommend that coronary artery calcium (CAC) screening should only be used for intermediate risk groups (Framingham risk score [FRS] of 10%-20%). The CAC distributions and coronary artery disease (CAD) prevalence in various FRS strata were determined. The benefit to lower risk populations of CAC score-based screening was also assessed. In total, 1,854 participants (aged 40-79 years) without history of CAD, stroke, or diabetes were enrolled. CAC scores of > 0, ≥ 100, and ≥ 300 were present in 33.8%, 8.2%, and 2.9% of the participants, respectively. The CAC scores rose significantly as the FRS grew more severe (P < 0.01). The total CAD prevalence was 6.1%. The occult CAD prevalence in the FRS ≤ 5%, 6%-10%, 11%-20%, and > 20% strata were 3.4%, 6.7%, 9.0%, and 11.6% (P < 0.001). In multivariate logistic regression analysis adjusting, not only the intermediate and high risk groups but also the low risk (FRS 6%-10%) group had significantly increased odds ratio for occult CAD compared to the very low-risk (FRS ≤ 5%) group (1.89 [95% confidence interval, CI, 1.09-3.29] in FRS 6%-10%; 2.48 [95% CI, 1.47-4.20] in FRS 11%-20%; and 3.10 [95% CI, 1.75-5.47] in FRS > 20%; P < 0.05). In conclusion, the yield of screening for significant CAC and occult CAD is low in the very low risk population but it rises in low and intermediate risk populations.
Aged ; Calcium/*analysis ; Coronary Artery Disease/*diagnosis/epidemiology/pathology ; Coronary Vessels/*chemistry/diagnostic imaging/metabolism ; Female ; Humans ; Logistic Models ; Male ; Middle Aged ; Multivariate Analysis ; Prevalence ; Risk Factors ; Severity of Illness Index ; Tomography, X-Ray Computed