The effect of age and risk factors on coronary and carotid artery atherosclerotic burden in males-Results of the Heinz Nixdorf Recall Study

Abstract

Background: Increased arterial intima-media thickness (IMT) and coronary artery calcification (CAC) are measures of subclinical arteriosclerosis burden. Little is known, however, whether risk factors have an impact differently on atherosclerosis in these distinct vascular territories in the same individuals.

Methods and design: For 1620 men without coronary artery disease (CAD) and stroke, aged 45-75 years (59+/-8), IMT was measured 1cm proximal to the bulb in the common carotid artery (CCA). Both sides were measured and the average of the right and left artery were applied. Electron-beam CT was used to quantify coronary artery calcium (CAC). Cardiovascular risk factors were measured with standard techniques.

Results: IMT increased with age from 0.64+/-0.12mm in the lowest decade (45-54 years) up to 0.76+/-0.14mm in the highest decade (65-74 years) (p<0.0001). CAC and IMT showed a significant correlation across the cohort. Individual variation in the extent of IMT and CAC was, however, high (r=0.26, p<0.0001). Standard risk factors had a similar impact on IMT and CAC relative to 5 years of ageing, except for diabetes and HDL, which had a higher impact on IMT than on CAC. The effect of diabetes mellitus on IMT exceeded the effect of 5 years of ageing.

Conclusions: IMT may be more sensitive to the atherosclerotic impact of diabetes than CAC, while blood pressure showed a higher effect on CAC. Thus, cardiovascular risk factors seem to have a different atherosclerotic impact on carotid arteries compared with coronary arteries.