Cross-sectionally assessed carotid intima-media thickness relates to long-term risk of stroke, coronary heart disease and death as estimated by available risk functions

Abstract

Objective. To relate cross-sectionally assessed indicators of carotid atherosclerosis measured in participants of the Rotterdam Study to absolute 10-12 year risks of stroke, coronary heart disease and death estimated by risk functions available from other studies. Setting. General population living in the suburb of Ommoord in Rotterdam, The Netherlands. Subjects. A sample of men and women (n = 1683), aged 55 years or over, drawn from participants from the Rotterdam Study (n = 7983). Main outcomes measures. Three risk scores were used to estimate for each individual the absolute risk of stroke, coronary heart disease and death within 10-12 years as a function of their cardiovascular risk factor profile. Cross-sectionally measured indicators of carotid atherosclerosis (presence of atherosclerotic lesions and common carotid intima-media thickness) were subsequently related to these risk scores. Results. The 10-year absolute risk of stroke increased linearly from 4.8% (95%CI = 3.8, 5.8) for subjects in the lowest quintile to 16.1% (12.3, 21.9) for subjects in the highest quintile of common carotid intima- media thickness distribution. Similarly, the 10-year absolute risk for coronary heart disease rose from 13.1% (95%CI = 12.0, 14.2) to 23.4% (95%CI = 21.4, 25.4), whereas the risk of death within 11.5 years rose from 15.0% (95%CI = 12.8, 17.4) in the lowest quintile to 46.0% (42.8, 49.3) in the upper quintile. The absolute risks of stroke, coronary heart disease or death rose from 8.8, 15.8 and 26.9% to 14.3, 19.8 and 40.9%, respectively, when plaques in the common carotid artery were present. Similar findings were observed for plaques in the carotid bifurcation. Conclusion. Common carotid intima-media thickness and carotid plaques are markers for increased risk of stroke, coronary heart disease and death within 10-12 years.