Prevalence of extracranial carotid artery disease detectable by echo-doppler in an elderly population

Little information is available on extracranial carotid artery disease in free-living elderly individuals. We sought to evaluate the prevalence of carotid lesions in the elderly. Using echo-Doppler, we assessed the prevalence of possible atherosclerotic lesions in the internal carotid arteries (n = 478) and the external and common carotid arteries (n = 956) of 239 subjects 65-94 years of age living in retirement homes in Seattle, Wash. We found that 152 (31.8%) internal carotid arteries were affected by nonstenosing plaque and 37 arteries (7.7%) had stenosis or occlusion. In addition, 193 (20.2%) external or common carotid arteries showed nonstenosing plaques. There were 128 subjects (53.6%) with internal carotid disease, 106 (44.3%) with evidence of external or common carotid disease, and 75 (31.4%) affected by disease in all three sites. There were 80 subjects (33.5%) with no ultrasound evidence of carotid disease. We found that the presence and severity of carotid disease increased between the decades 65-74 and 75-84. We also demonstrated a positive association between systolic blood pressure and ultrasound evidence of carotid disease that was independent of age. The prevalence of extracranial artery disease in an apparently healthy population was high, although stenoses in most instances were not severe. We conclude that noninvasive ultrasound methods identify a relatively small fraction of individuals (5% of the total) at high risk for stroke or transient ischemic attack. Echo-Doppler might be used to monitor further disease progression and to evaluate the efficacy of different therapeutic or preventive interventions.