Abstract 359: Duke Activity Status Index is Sensitive to Non-Fatal Adverse Cardiac Events when Evaluating Patient Outcome at Late Follow-up

Abstract

Objective: The Duke Activity Status Index (DASI) questionnaire has become an established measure of cardiac functional capacity and quality of life. However, the relationship between a low DASI score and presence of major adverse cardiac events has not yet been assessed. This study evaluates differences in patient function and occurrence of late cardiac events in patients undergoing coronary artery bypass (CAB). Methods: Patients undergoing CAB between 1994 and 2014 at the Valley Hospital were assessed and propensity matched for surgical approach. The resulting population of 1856 patients was followed for a mean time of 11.2 years ranging from 1 to 20 year. Survival, occurrence of MI, stroke, repeat revascularization and patient function using the DASI questionnaire were assessed. At the latest follow-up, 1363 patients were still alive, of which 776 had completed the DASI questionnaire. Patients who completed the questionnaire (Responders) were compared to those who did not complete the DASI (Non-Responders) on baseline demographic and clinical characteristics. Kaplan-Meier and Cox Proportional Hazards Regression were used to compare late non-fatal events that occurred in patients with a low (<37, N=247), medium (37-52, N=209), or high (>52, N=310) DASI score. Results: Responders had a higher rate of prior MI, increased hypertension, and were significantly older at baseline procedure compared to Non-Responders. Both groups had comparable surgical risk and left ventricle ejection fraction at baseline revascularization. Kaplan-Meier analysis of the Responders showed that patients with a low scoring DASI had significantly greater occurrence of all late events. Cox Regression analysis controlling for all baseline factors showed that patients with a low DASI score had a two-fold increase in late non-fatal events compared to medium and high DASI scoring patients (adjusted hazard ratio: 2.076, 95% C.I. 1.309-3.293, p=0.002) (Figure 1). Conclusions: This study demonstrates that in cardiac surgical patients, a low score on DASI is independently associated with a higher occurrence of late non-fatal cardiac events. This provides further evidence supporting the use of the DASI questionnaire in evaluating patient functioning after cardiac surgery.