Abstract 492: Clinical Outcomes of Individuals With Discordance Between the Framingham Risk Score and the Coronary Artery Calcification Score
Background: Traditional tools used to assign risk of future cardiovascular events, at times fail to accurately identify individuals with severe coronary artery disease. Clinical outcome of patients with discordance between the Framingham risk score (FRS) and the coronary artery calcium score (CAC) are poorly defined. We studied the discordance between FRS and CAC. Significant CAC (CAC>100) is associated with a striking increase in cardiovascular events (hazard ratio>10) making it an excellent surrogate marker.
Methods: Seven hundred and thirty subjects (age 61 ± 10 years, 12.8% female) who underwent CAC were studied. Subjects were classified as “discordant low risk” (DLR) if the FRS <10% and CAC ≥100 (n = 108, 14.8%) or “discordant high risk” (DHR) if the FRS ≥20% and CAC = 0 (n = 104, 14.2%). Cox proportional hazard models were used to examine the CVD mortality risk associated with CAC score among subjects classified as “low risk” based on FRS.
Results: Compared with DHR, DLR were at increased risk for CVD mortality (hazard ratio: 3.8, 95% CI 1.6 – 8.2 p = 0.003). In addition, the event free survival was 92.2% for DHR and 81.7% for DLR over a mean 50 year follow up period. (Figure⇓)
Conclusion: The FRS falsely classified a sizeable group of individuals in our cohort who were found to be at high risk for future cardiac events. These findings highlight the need for more refined methods to calculate the risk of future cardiac events.