Relationship Among Risk Score Systems and Coronary Atherosclerosis Determined by Multislice Computed Tomography

Risk score systems (RSS) were designed to estimate the risk of cardiac events. Their ability to predict coronary atherosclerosis (CA) has not been established.

Risk score systems can predict presence of CA in patients without typical symptoms or ischemia. Because design of each RSS is different, their predictive value could also differ.

A retrospective analysis was done on patients from a low-risk region referred for cardiac multislice computed tomography (MSCT). The sample included low- to intermediate-risk patients with nontypical chest pain and asymptomatic high-risk patients. Patients with documented ischemia were excluded. Three RSS were determined: Framingham Risk Score (FRS), Regicor (FRS calibrated for Spanish population), and Systematic Coronary Risk Evaluation (SCORE). Coronary arteries were investigated to determine calcium score and presence of protruding atheromas.

We analyzed 582 patients (53.8% male; mean age 51 ± 11.5 years). Their mean estimated risk was intermediate: 15.6 ± 10.4 by FRS, 6.3 ± 4.3 by Regicor, and 3.9 ± 4.1 by SCORE. The MSCT showed no CA in 38.8%, nonobstructive plaques in 28.7%, and obstructive ones in 32.5%. The ability of the RSS to predict CA was not significantly different, with moderate diagnostic value (areas under ROC curves, 0.72-0.65). The prevalence of CA was high in low-risk patients: 40%, 47%, and 53% in FRS, Regicor, and SCORE low-risk patients, respectively.

Risk score systems have only moderate diagnostic value to predict presence of CA, without significant differences among them. Coronary artery disease is highly prevalent in patients considered low risk.