Differences in the effect of cigarette smoking on endothelial function in chinese and white adults.
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.


OBJECTIVE
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.


METHODS
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).


METHODS
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).


CONCLUSIONS
Young Chinese adults have less evidence of arterial endothelial dysfunction than young white adults with similar direct or indirect exposure to cigarette smoke.
Woo
K S
KS
Chinese University of Hong Kong, Hong Kong.
Robinson
J T
JT
Chook
P
P
Adams
M R
MR
Yip
G
G
Mai
Z J
ZJ
Lam
C W
CW
Sorensen
K E
KE
Deanfield
J E
JE
Celermajer
D S
DS
D000293:Adolescent; D000328:Adult; D001158:Arteries / Q000503:physiopathology; D044466:Asian People; D001315:Australia; D002681:China; D015986:Confounding Factors, Epidemiologic; D004730:Endothelium, Vascular / Q000503:physiopathology*; D004739:England; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012907:Smoking / Q000009:adverse effects*; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D014664:Vasodilation; D044465:White People
D014028:Tobacco Smoke Pollution