Abstract P362: Left Atrial Dimension and Global Cardiovascular Framingham 10 Year Risk Score Predicting 20-year Clinical Cardiovascular Events in Young Healthy Adults: The CARDIA Study
OBJECTIVE An enlarged left atrial dimension (LAD) is associated with incident cardiovascular (CV) outcomes. However, the incremental value of LAD over Framingham risk score (FRS) in young adults is unclear. We investigate whether adding information about LAD would improve CV risk prediction in young adults beyond the FRS.
METHODS The Coronary Artery Risk Development in Young Adults (CARDIA) study enrolled 5115 African-American and White adults from 4 US centers in 1985-1986. CARDIA year-5 exam was defined as baseline, when the cohort underwent first echocardiography assessment. Participants were divided in low, intermediate, and high risk groups for FRS <2.5%, 2.5-15%, and >15%, respectively. LAD was assessed by M-mode echocardiography and indexed by height (LADi). The combined endpoint of the first CV outcome included: cardiovascular death, or nonfatal heart failure, myocardial infarction, or stroke. We assessed calibration and discrimination, as well as global and stratified net reclassification improvement (NRI) for adding LADi to FRS.
RESULTS A total of 4082 participants were included; aged 30±4 years, 46% males, and 52% White. The mean±SD value of LADi was 2.07±0.27 mm/m. 123 participants (3%) had outcomes over the following 20 years. Event incidence across FRS low, intermediate, and high risk groups was 1.3%, 5.3%, and 22.4%; changing to 1.08%, 5.56%, and 22.67% with the addition of LADi to FRS categories. Adjusted for FRS, the hazard ratio for each 1 SD increase in LADi predicting outcomes was 1.27 (95% confidence interval: 1.07, 1.51). Adding LADi modestly increased the area under the ROC curve compared to FRS alone (0.759 to 0.772, p = 0.04). NRI showed improvement by adding LADi to the FRS, particularly in the low and intermediate risk groups (Table).
CONCLUSION In young adults, the FRS is a robust CV risk marker based on clinical parameters. LAD, as an early marker of increased ventricular filling pressures, may add relevant information to FRS predicting CV outcomes.
- © 2013 by American Heart Association, Inc.