Prognostic Value of Combination of Plasma D-Dimer Concentration and Estimated Glomerular Filtration Rate in Predicting Long-Term Mortality of Patients With Stable Coronary Artery Disease

Background: A modestly elevated circulating D-dimer level may be relevant to coronary artery disease (CAD), but its prognostic value, both independently and in combination with estimated glomerular filtration rate (eGFR), for long-term death has not been fully evaluated in stable CAD patients. Methods and Results: Baseline plasma D-dimer levels and eGFR were measured in 1,341 outpatients (mean age: 65 years) with prior myocardial infarction (MI), coronary revascularization, and/or angiographic evidence of a significant stenosis (> 50%) for at least one of the major coronary arteries. Among these patients, 43% had prior MI, 47% had prior coronary revascularization, 41% had multivessel CAD, 14% had paroxysmal or persistent atrial fibrillation, 32% had diabetes, and 32% had chronic kidney disease (eGFR < 60 mL/min/1.73 m2). D-dimer levels weakly correlated with eGFR (r=-0.25; P< 0.0001). During a mean follow-up period of 73 months, there were 124 deaths, including 61 cardiovascular deaths. Multivariate Cox regression analysis identified D-dimer levels (P=0.001) and eGFR (P=0.006) as independent predictors of all-cause death. Adding both D-dimer and eGFR to a baseline model with established risk factors improved the net reclassification (P< 0.005) and integrated discrimination improvement (P< 0.05) greater than that of any single biomarker or baseline model alone. Conclusions: The combinatorial value of assessing D-dimer levels and eGFR may provide useful insight regarding stable CAD patients' long-term risk stratification.