Abstract 2763: Predictive Value of Ankle-Brachial-Index and Plaques in the Carotid and Femoral Arteries on Cardiovascular Events and Mortality in a Population-Based Study with 13-Years of Follow-Up
Background: Peripheral arterial occlusive disease (PAOD) is associated with a high risk of cardiovascular morbidity and mortality. However, long-term prospective population-based studies on the value of Ankle-Brachial-Index (ABI), an excellent indicator of atherosclerotic burden, in subjects with asymptomatic PAOD are still sparse. Therefore, in this large random subsample of the general population from Southern Germany, we prospectively investigated the predictive value of ABI and presence of plaques in the carotid and femoral arteries for future myocardial infarction (MI), cardiovascular and total mortality during a 13 year follow-up.
Methods: Ultrasonography for the presence of plaques in carotid and femoral arteries and measurement of ABI has been performed in 1325 initially healthy participants of the population-based MONICA Augsburg Study conducted in 1989/90. ABI was calculated as the ratio of the systolic blood pressure at each ankle to the systolic blood pressure at the right arm, using a Doppler ultrasonic device and a blood pressure cuff.
Results: At baseline, 6.1% of men and 2.6% of women had an ABI≤0.9. At least one plaque in the carotid or femoral arteries was identified in 51.8% of men and 36.3% of women. During a 13 year follow-up, 58 persons suffered an MI before age 75, 189 persons died, 86 of them from cardiovascular causes. Kaplan-Meier curves showed that an ABI < 0.9 and/or presence of plaque were strong predictors for all three endpoints (p<0.0001). Cox regression analysis revealed a hazard ratio (HR) per 0.1-unit ABI increment for MI of 0.82 (p=0.012), and for cardiovascular and total mortality of 0.74 and 0.76 (p<0.00001), respectively. Correction for measurement error in ABI considerably increased these estimates. The HR for each increase in the number of plaque-affected arteries was 1.52, 1.70 and 1.45 for MI, cardiovascular and total mortality, respectively (p<0.0001).
Conclusion. Both, ABI and number of plaque-affected arteries were strong predictors for MI, cardiovascular and total mortality in the initially asymptomatic subjects from general population.