Prevalence of Carotid Artery Disease among Ambulatory Patients with Coronary Artery Disease

Background: Concomitant carotid artery disease (CaAD) in patients with coronary artery disease (CAD) is associated with worse cardiac and neurologic outcomes. The reported prevalence and risk factors for concomitant CaAD in CAD patients varied among previous studies. Objectives: To examine these factors in ambulatory patients with CAD and well-documented cholesterol levels treated with cholesterol-lowering medications. Methods: We retrospectively analyzed prospectively collected data from 325 unselected patients with CAD (89 women, mean age 68.8 +/- 9.9 years) undergoing routine evaluation at the coronary clinic of our hospital. Results: The low density lipoprotein-cholesterol (LDL-C) was < 100 mg/dl in 292 patients (90%). Age at onset of CAD symptoms was 59.4 +/- 10.8 years. Carotid stenosis >= 50% was seen in 83 patients (25.5%) and between 30% and 49% in 55 patients (17%) (duplex method). Carotid stenosis was significantly associated with hypertension (P = 0.032), peripheral arterial disease (P = 0.002) and number of coronary arteries with 50% stenosis (P = 0.002), and showed a borderline association with age at CAD onset (P = 0.062) and diabetes mellitus (P = 0.053). On linear regression analysis, independent predictors of CaAD were peripheral vascular disease (OR 3.186, 95%Cl 1.403-7.236, P = 0.006), number of coronary arteries with 50% stenosis (OR 1.543, 95%Cl 1.136-2.095, P = 0.005), and age at CAD onset (OR 1.028, 95%Cl 1.002-1.054, P = 0.003). None of the variables studied predicted freedom from CaAD. Conclusions: Carotid atherosclerosis is very common in stable ambulatory patients with CAD regularly taking statins. The risk is higher in patients with peripheral arterial disease, a greater number of involved coronary arteries, and older age at onset of CAD.