Increased carotid wall thickness measured by computed tomography is associated with the presence and severity of coronary artery calcium

Abstract

BackgroundPrevious studies have shown that increase in carotid wall thickness (CWT) is associated with cardiovascular risk factors. However, simultaneous systemic and local involvement of atherosclerosis in subjects with high risk of coronary atherosclerosis is not well studied. This study investigates the relation of carotid subclinical atherosclerosis assessed by CWT with the presence and severity of coronary artery calcium(CAC). MethodsOne hundred and twenty nine subjects (age of 69±10 years, 72% male) underwent CAC, carotid CT angiography, and their metabolic status was evaluated. CAC was defined as 0, 1–100, 101–400, 401–1000 and 1000+. CWT (mm) was calculated as: [mean of both right and left CT−measured CWT 10-mm below the common carotid bifurcation]. ResultsModest correlation between CWT and CAC was noted (r=0.48, p=0.0001). CWT increased substantially with the severity of CAC from CAC 0 to CAC 1000+ (p<0.05). Increased CWT (1.0 mm+) was more prevalent in subjects with significant CAC (100+) as compared to CAC 0 (44.7% vs. 3.3%, p<0.05). Increase in CWT was associated with increased rates of metabolic syndrome and diabetes mellitus. After adjustment for cardiovascular risk factors, the risk of metabolic syndrome and DM was 1.7 and 2.3 respectively for each standard deviation (SD) increase in CWT. Similarly, the risk for each SD increase in CWT increased with severity of CAC as compared to CAC 0 (RR:CAC 1–100:1.2, CAC 101–400:1.5, CAC 400–1000:2.1, and CAC 1000+:3.4, respectively). ConclusionIncreased CWT is associated with the presence and severity of CAC, metabolic syndrome and DM independent of conventional cardiovascular risk factors; highlighting the important role of comprehensive carotid and coronary atherosclerotic assessment to identify at-risk individuals.