Abstract 14347: An Externally Validated Community-Based Risk Prediction Score for Sudden Cardiac Death
Introduction: Sudden cardiac death (SCD) is a leading cause of death in the United States, and many victims are not identified as at-risk for SCD with existing screening tools. The objective of this study was to derive and validate a population-based risk assessment score for prediction of SCD.
Methods: The Atherosclerosis Risk in Communities (ARIC) cohort is comprised of men and women from four US communities, aged 45-64 at baseline; 11,335 white participants (mean age 54.4 years, 52.4% women) were included in the analysis. SCD was physician-adjudicated and defined as death due to coronary heart disease within one hour of symptom onset. Cox proportional hazards models were used to derive an equation to estimate SCD risk within 10 years. Covariates were selected from among commonly available demographic and clinical variables using Akaike’s Information Criteria. The utility of the final risk score was assessed by calculating discrimination (Harrell’s c-index) and calibration (Hosmer-Lemeshow chi-square test). The risk score was validated among 5,626 Framingham Heart Study and Framingham Offspring Study participants (mean age 48.2 years, 52.8% women), aged 30 to 70 years.
Results: During 10 years’ follow up among ARIC participants, 95 participants experienced SCD; the majority (65%) occurred in the highest quintile of predicted risk. Selected covariates for the model included age, sex, total cholesterol, lipid-lowering medication use, hypertension medication use, systolic and diastolic blood pressure, smoking status, diabetes, and body mass index. The risk score yielded very good discrimination in ARIC (c-index: 0.82, 95% CI: 0.78-0.85) and Framingham (c-index: 0.82, 95% CI: 0.79-0.86). Calibration plots indicated excellent calibration in ARIC (χ2: 5.3, p= 0.82) but poorer in Framingham (χ2: 29.7, p<0.001); a simple recalibration led to excellent fit (χ2: 2.1, p= 0.99) within Framingham.
Conclusions: We derived and externally validated a sex-adjusted risk prediction score for SCD. The proposed risk score has strong discrimination and calibration in the derived population, and may be used to identify those at risk for SCD within 10 years, and particularly screen for those at highest risk.
Author Disclosures: B. Bogle: None. J.J. Goldberger: None. S. Mehrotra: None. H. Ning: None. D.M. Lloyd-Jones: None.
- © 2016 by American Heart Association, Inc.