Relationship between carotid intima-media thickness and symptomatic and asymptomatic peripheral arterial disease - The Edinburgh Artery Study

Background and Purpose Ultrasonic evaluation of intima-media thickness (IMT) is one method of assessing the development of early atherosclerosis. This report describes the distribution of IMT within the general population and is one of the first to investigate its association with noninvasively assessed symptomatic and asymptomatic peripheral arterial disease. Methods Ultrasonic evaluation of IMT was included in the 5-year follow-up examination of participants of the Edinburgh Artery Study. Valid readings of IMT were recorded in 1106 subjects aged 60 to 80 years, and the maximum from the right and left sides of the neck was used in tile analysis. Existing symptomatic and asymptomatic peripheral arterial disease and coronary heart disease were also assessed at follow-up using previously validated noninvasive techniques. Results IMT increased continuously with age (P less than or equal to.01), and its distribution was positively skewed in both sexes. The results suggest that levels of atherosclerotic development in the common carotid artery are 5 to 10 years more advanced in men than in women. In this population, the overall prevalence of moderate to severe disease was very low (only 1.2% of study participants had IMT values >2 mm). The presence of symptomatic (intermittent claudication) or asymptomatic (ankle brachial pressure index less than or equal to 0.9) peripheral arterial disease was significantly associated with increased IMT (P less than or equal to.05). Conclusions Although tile prevalence of advanced atherosclerosis was very low. small changes in IMT were associated with clinically significant development of atherosclerosis in the peripheral arteries. However, further longitudinal studies are needed that standardize measurement techniques and would allow accurate comparisons across studies.