Carotid intima-media thickness in plaque-free area, carotid plaque and risk of ischemic stroke in high-risk population of North China.

OBJECTIVE: Stroke is the leading cause of mortality and acquired disability in adults in China. In this study, we investigated the role of carotid artery intima-media thickness (IMT) and carotid plaques in new ischemic stroke of high-risk population in North China.
METHODS: The study was conducted in 4 towns in North China area. Subjects with three or more cardiovascular risk factors such as hypertension, dyslipidemia (or unknown), diabetes mellitus, currently smoking, over weight, family history of stroke, with a history of transient ischemic attack (TIA) and ischemic stroke were included in this study. The demographic data, carotid artery-IMT and number of segments with plaques (NSP) was recorded when they were recruited. The new ischemic stroke was recorded in 2129 subjects after 2.1 year's follow up. Risk analysis was performed between subject with or without new ischemic stroke.
RESULTS: There were 69 new cases occurred ischemic stroke. The proportion of hypertension, ischemic stroke history and the plaque numbers were significantly higher in subjects with new ischemic strokes than those without new ischemic strokes. Cox regression showed remarkable positive correlation between the incidence of new ischemic stroke events with the presence of plaque as well as increased NSP. However, the increasing quartiles of common carotid artery intima-media thickness (CCA-IMT) has no difference in occurrence of new ischemic stroke events.
CONCLUSION: Screening of carotid artery especially for carotid artery plaques should be taken into consideration among people with high risk of ischemic stroke.