To the Editor: Dr Polonsky and colleagues1 demonstrated that CACS significantly improved classification of future coronary heart disease (CHD) risk when added to traditional risk factors. It would be helpful if the authors report further how they actually used CACS to reclassify risk. It appears that they used the ln(CAC + 1) value to increase the 5-year predicted risk in model 2; however, it is less clear how risk was reclassified downwards on the basis of CACS. Knowledge of the mechanism by which they used CACS to reclassify risk will facilitate future comparative studies and provide a foundation for a potential randomized controlled trial.
McEvoy JW. Coronary Artery Calcium Score and Cardiovascular Event Prediction. JAMA. 2010;304(7):741-742. doi:10.1001/jama.2010.1143