atherosclerotic cardiovascular disease risk based on SCore algorithms and reclassification based on preclinical atherosclerotic plaques

Background: The aim of this study was to determine the efficacy of the number of carotid and common femoral bifurcations with plaque (NBP) detected by ultrasound in reclassifying atherosclerotic cardiovascular disease (ASCVD) risk obtained from SCORE algorithms. Data from the cohort of 1000 individuals free from ASCVD in the Cyprus Epidemiological Study on Atherosclerosis was used. Methods: In each predicted ASCVD risk class (low, moderate, high) based on SCORE algorithms and baseline data, the observed 10-year risk of subgroups according to the NBP was used to reclassify participants. Results: There were 222 ASCVD events during a mean follow-up of 15.2±4.9 years. In each predicted risk class, the observed 10-year ASCVD event risk increased progressively in the subgroups across the presence of 1, 2, 3 and 4 bifurcations with plaque (P<0.001); Hazard Ratios (crude and adjusted for conventional risk factors) also increased progressively (P<0.001). There was a correct down classification in 152 and correct up classification in 99 participants. Total correct reclassification improvement was in 251 (25.1%). Conclusions: The results demonstrate that the NBP which is easy to detect is an independent predictor of ASCVD events and can be used to reclassify individuals into a different risk class by improving on the predicted SCORE risk.