Carotid atherosclerosis and the risk factors in early postmenopausal Chinese women

Abstract

OBJECTIVES: To describe the distribution of intima-media thickness (IMT) and the prevalence of plaque by carotid segments, walls and sides, and to examine their associated risk factors in asymptomatic, early postmenopausal Chinese women in Hong Kong. METHODS: Between 2002 and 2004, the study recruited 518 postmenopausal women aged 50-64 years. They were examined by B-mode ultrasound to measure the IMT and the prevalence of plaque at the near and far walls of common carotid (CCA), bifurcation (bulb), and internal carotid (ICA) of both the left and right carotid arteries. Blood pressures, obesity indices, lipids and glucose levels, sociodemographic, medical and lifestyle factors were also obtained. RESULTS: The mean IMT was 0.76+/-0.12 mm (range: 0.53-1.33 mm). IMT was significantly thicker on the far wall than on the near wall and differed among segments (being thickest at the bulb and the narrowest at the ICA). 21.8% had at least one plaque in the carotid artery with most of the plaque found at the bulb area. Systolic blood pressure had statistically significant relationship with IMT that were fairly homogeneous among different segments. Lipids were associated with the CCA and bulb IMT, but not the ICA IMT. Diabetes predicted only CCA IMT. Older age, higher waist-hip-ratio and low-density lipoprotein cholesterol were significant predictors of plaques at all sites combined. CONCLUSIONS: We described the distribution of IMT and the prevalence of plaque in asymptomatic, early postmenopausal Chinese women. Associations of risk factors with IMT of different arterial segments were also observed.