Background: Carotid arterial intimal-medial thickness (IMT) measured by high-resolution B-mode ultrasonography has come to be used as a noninvasive surrogate end point to measure progression of atherosclerosis. However, there are no detailed data on the relationship between aggregation of coronary risk factors and carotid atherogenesis.
Methods: Cross-sectional assessment of the relationship between carotid atherosclerosis detected by high-resolution ultrasonography and integration of major coronary risk factors by age and sex. Subjects aged 30 to 86 years were randomly selected from Suita, located in Osaka, the second largest urban area of Japan, including 1896 men and 2102 women. Carotid atherosclerosis was evaluated by using our atherosclerotic indexes of IMT, plaque number, plaque score, and percentage of stenosis of the carotid artery assessed using ultrasonography by sex and age group classified by number of major coronary risk factors (ie, hypertension [diastolic blood pressure > or =90 mm Hg and/or systolic blood pressure > or 140 mm Hg or receiving medication], smoking [current smoker], and hypercholesterolemia [serum total cholesterol level > or =5.68 mmol/L [220 mg/dL] or receiving medication]).
Results: The mean carotid atherosclerotic index value, especially the mean IMT value, of the subjects with 1 major coronary risk factor was on average 0.028 mm (3.2%) higher for men and 0.025 mm (2.9%) higher for women than that of the subjects without major coronary risk factors; for subjects with 2 risk factors, 0.054 mm (6.3%) higher for men and 0.053 mm (6.2%) higher for women; and for high-risk subjects with 3 major risk factors, 0.135 mm (15.8%) higher for men and 0.137 mm (15.4%) higher for women. The percentage of the subjects with severe stenosis of at least 50% increased stepwise with increases in the number of coronary risk factors and showed a significant difference (P<.05) between men and women, ie, 2.4% vs 0. 6% (P =.01) among the subjects with no risk factors; 6.7% vs 1.5% (P<.001), subjects with 1 risk factor; 10.7% vs 2.7% (P<.001), subjects with 2 risk factors; and 18.6% vs 5.0% (P =.01), high-risk subjects.
Conclusions: Aggregation of established major coronary risk factors strongly influenced carotid atherogenesis in both sexes. There were significant differences between sexes in the acceleration or progression of carotid atherosclerosis.