Prognostic Value of Estimated Functional Capacity Incremental to Cardiac Biomarkers in Stable Cardiac Patients

BACKGROUND: Few studies have investigated functional capacity self‐assessment tools in either prediction of future major adverse cardiac outcomes beyond all‐cause mortality or direct comparisons with clinically available biomarkers. METHODS AND RESULTS: We estimated functional capacity using the Duke Activity Status Index (DASI) questionnaire in 8987 sequential stable patients without acute coronary syndrome who were undergoing elective diagnostic coronary angiography with 3‐year follow‐up of major adverse cardiac events (death, nonfatal myocardial infarction, or stroke). A low DASI score provided independent prediction of a 4.8‐fold increase in future risk of incident major adverse cardiac events at 3 years (quartiles 1 versus 4 hazard ratio [95% CI] 4.76 [4.03 to 5.61], P<0.001), and a 3.8‐fold increased risk after adjusting for traditional risk factors (3.77 [3.15 to 4.51], P<0.001). The prognostic value of the DASI score was evident in both primary and secondary prevention cohorts, with and without heart failure, as well as high and low C‐reactive protein and B‐type natriuretic peptide levels. The DASI score reclassified 15% of patients (P<0.001) beyond traditional risk factors in predicting future MACE. CONCLUSION: A simple self‐assessment tool of functional capacity in stable patients undergoing elective diagnostic cardiac evaluation provides independent and incremental prognostic value for prediction of both significant coronary angiographic disease and long‐term adverse clinical events.