Risk factors and concomitants of internal carotid artery occlusion or stenosis. A controlled study of 159 cases.

Presumed risk factors were studied in 159 patients with internal carotid artery (ICA) occlusion or stenosis. Smoking, family history of strokes, ischemic changes on electrocardiogram, and obesity were more frequent and blood pressure and plasma glucose levels were higher than in 159 sex- and age-matched controls. Blood pressure and plasma glucose levels were higher and smoking was more frequent in patients with occlusion than in those with stenosis. These points suggest that progression is related to some of the precursors of atherosclerosis. No difference was found between the patients with ICA disease and an age- and sex-matched group who had coronary disease without carotid disease, except for diabetes, which was more frequent in ICA occlusion, and for family history, which corresponded to the site of atherosclerosis (carotid vs coronary). The constitutional basis may be the most important differential risk factor in ICA vs coronary disease.