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Objective: Arterial endothelial dysfunction is a key atherogenic event that may be related to oestrogen status. We therefore aimed to compare menopause-related changes in endothelial physiology in Chinese and Caucasian females., Methods: We studied 40 female subjects; 20 Chinese from a rural region of Southern China (ten premenopausal, aged 20-35 years, and ten postmenopausal, aged 55-66 years), and 20 age-matched Caucasian females from Sydney, Australia. All women had a clinical history, resting blood pressure and fasting lipids measured, and endothelial function assessed. Using high-resolution external vascular ultrasound, brachial artery diameter was measured at rest, after flow increase (causing endothelium-dependent dilatation) and after sublingual glyceryl trinitrate (GTW) (an endothelium-independent dilator)., Results: There was a significant decline in endothelium-dependent dilatation (EDD) comparing Caucasian females from the premenopausal versus postmenopausal groups (8.4+/-2.7% versus 2.7+/-2.9%; P<0.001). In contrast, there was no significant difference in EDD between pre- and postmenopausal Chinese (9.8+/-3.3% versus 8.3+/-1.7%; P=0.22). On multivariate analysis, postmenopausal status was associated with impaired EDD in Caucasian females (P<0.002) independent of serum cholesterol, blood pressure and vessel size. In contrast, EDD in the Chinese females was not significantly influenced by any of these factors. GTW-induced dilatation was also impaired in the older Caucasian females, a finding explained on multivariate analysis by the increased vessel size in this patient group (P=0.03)., Conclusion: Menopause is associated with impaired arterial endothelial function in Caucasian but not Chinese women. This suggests possible ethnic differences in menopause-related vascular changes.

Cardiovascular event rates are much lower in China compared with developed countries. "Westernization" of diet and lifestyle in the Chinese, however, may lead to an increased prevalence of atherosclerosis-related diseases. Because carotid intima-media thickness (IMT) is a marker of subclinical atherosclerosis, we examined IMT and vascular risk profile in community-based groups of rural Chinese, Westernized urban Chinese, and urban whites. Mean IMT of the common carotid artery was measured in 348 healthy adults, aged 42+/-13 years (range 21 to 71 years); 116 subjects from rural China, 116 urban Chinese subjects living in Hong Kong or in Australia, and 116 urban Caucasians living in Australia. These 3 groups were matched for age, sex, and cigarette smoke exposure. Urban Chinese subjects had slightly better risk factor profile (higher HDL-cholesterol and lower blood pressure) compared with rural Chinese subjects. Despite this, however, the mean IMT was lowest in rural Chinese (0.50+/-0.10 mm), intermediate in urban Chinese (0.56+/-0.12 mm), and highest in urban whites (0.64+/-0.13 mm) (P<0.001 for comparisons between all groups). These differences in IMT were not altered after adjustment for the major traditional cardiovascular risk factors (serum lipids, smoking, and blood pressure or for body mass index). The influence of vascular risk factors on atherosclerosis between urban versus rural Chinese subjects was studied by multivariate regression models and by comparing the steepness of regression slopes between risk factors and IMT in the subject groups. The effects of smoking, HDL-cholesterol, and triglycerides on IMT were significantly greater in the urban compared with the rural Chinese (P<0.01). These data suggest that Westernization of Chinese subjects is associated with greater susceptibility to the pro-atherogenic effects of traditional vascular risk factors, such as lipids and smoking, and with evidence of increased IMT as a marker of subclinical atherosclerosis.

Background: The prevalence of coronary artery disease in southern China is approximately one fifth that in "westernized" countries, even though approximately 70% of Chinese men smoke cigarettes and Chinese women have substantial passive exposure to cigarette smoke., Objectives: Endothelial dysfunction is an early event in atherosclerosis and occurs in young white active and passive smokers; we compared endothelial physiology in healthy young Chinese and white smokers and nonsmokers., Patients: 144 healthy adults who were 16 to 45 years of age: 72 Chinese persons in a village in southern China and 72 white persons in Australia and England who were matched for exposure to cigarette smoke. Each ethnic group comprised 36 controls (lifelong nonsmokers with no regular exposure to cigarette smoke; 16 men and 20 women) and 36 active or passive smokers (15 men and 21 women)., Measurements: Arterial endothelial function was tested with high-resolution external vascular ultrasonography, and brachial artery diameter was measured at rest, after flow increase (which causes endothelium-dependent dilatation), and after administration of sublingual nitroglycerin (an endothelium-independent dilator)., Results: Endothelium-dependent dilatation was similar in Chinese (7.9%) and white (8.4%) nonsmokers (P > 0.2). Among white persons, endothelium-dependent dilatation was lower in active or passive smokers (3.9%) than in nonsmokers (8.4%) (P < 0.001). Among Chinese persons, dilatation was not significantly lower in active or passive smokers (7.3%) than in nonsmokers (7.9%) (P > 0.2). Dilatation was higher in Chinese active or passive smokers (7.3%) than in white active or passive smokers (3.9%) (P < 0.001). Dilatation responses to nitroglycerin were similar in all groups (P = 0.17)., Conclusion: Young Chinese adults have less evidence of arterial endothelial dysfunction than young white adults with similar direct or indirect exposure to cigarette smoke.

Objectives: We sought to assess the effects of aging on the endothelial physiology of a group of Chinese adults., Background: Several studies have documented an association between aging and progressive arterial endothelial dysfunction in white subjects. We hypothesized that age-related endothelial dysfunction, an important event in atherosclerosis, might be less marked in southern Chinese subjects, in whom the prevalence of coronary heart disease is only approximately 20% of that in industrialized countries., Methods: We studied endothelial function in 76 healthy adults aged 16 to 70 years: 38 Chinese from a village of 3,000 people in southern China and 38 white subjects from Sydney, Australia. In each ethnic group, there were 19 younger persons (16 to 40 years) and 19 older adults (55 to 70 years). None had evidence of diabetes, hypertension or clinical vascular disease or had ever been regular cigarette smokers. With the use of high resolution external vascular ultrasound, brachial artery diameter was measured at rest, after flow increase (causing endothelium-dependent dilation) and after sublingual nitroglycerin (an endothelium-independent dilator)., Results: Endothelium-dependent dilation was similar in young Chinese (mean +/- SD 8.3 +/- 2.5%), young whites (7.9 +/- 2.0%) and older Chinese (6.8 +/- 2.9%), but it was significantly impaired in older whites (1.8 +/- 2.5%, p < 0.001 by analysis of variance). On multivariate analysis, older age was associated with impaired endothelium-dependent dilation (p < 0.001) (independent of the effects of serum cholesterol, gender and vessel size) in the white but not in the Chinese subjects (p = 0.83). Nitroglycerin-induced dilation was not significantly different with aging in either ethnic group., Conclusions: Endothelium-dependent dilation is similar in the arteries of healthy young Chinese and white adults. With older age, however, Chinese subjects are less susceptible to impaired endothelial function.