Abstract 17185: Dose-response Gradient Between Levels of Newly Revealed, Asymptomatic Abnormal Ankle-Brachial Index and Clinical Events in Patients With Significant Coronary Artery Disease
Objectives: The aim of the present study was to evaluate dose-association between levels of newly revealed abnormal ankle-brachial index (ABI) and clinical outcomes in patients with significant coronary artery stenosis.
Methods: Between January, 2006, and December, 2009, ABI was evaluated in 2,543 consecutive patients with no clinical history of claudication or peripheral artery disease who underwent diagnostic coronary angiography. Abnormal ABI was defined as ≤0.9 (low) or ≥1.4 (high). The primary endpoint was the composite of death/myocardial infarction/stroke over 3 years.
Results: Of the 2,424 patients with at least one significant stenosis (≥50%) in a major epicardial coronary artery, 385 (15.9%) had abnormal ABI, including 348 (14.4%) with ABI ≤0.9 and 37 (1.5%) with ABI ≥1.4. During a median follow-up of 986 days, the 3-year major adverse event rate was significantly higher in patients with abnormal than normal ABI (15.7% vs. 3.3%, p<0.001). The risk for death/MI/stroke at 3-year for different levels of ABI compared with a normal ABI of 0.91 to 1.40 formed a reverse J-shaped curve. (Figure A) According to the low, normal and high ABI group, there were significant differences in 3-year event rate (3.3% in normal, 10.2% in high and 16.2% in low ABI group, log-rank p-value<0.001). (Figure B) After multivariate adjustment, low ABI group showed also significant risk (adjusted HR, 1.59; 95% CI, 1.10 to 2.50; p-value=0.047) but in high ABI group showed higher trend without statistical significance. (Adjusted HR, 1.72; 95% CI, 0.65-4.54; p-value=0.27) (Figure C, D)
Conclusions: There was a significant dose-response gradient between abnormal ABI values and adverse events, comparing with normal ABI.
- © 2013 by American Heart Association, Inc.