Associations of polymorphism of P22(phox) C242T, plasma levels of vitamin E, and smoking with coronary heart disease in China.
BACKGROUND
The C242T polymorphisms of P22(phox) and plasma vitamin E have been associated with the risk of coronary heart disease (CHD) in several studies, but the results have been inconsistent. In this study, we sought to examine potential interactions between P22(phox) genotypes, plasma vitamin E concentrations, and smoking in relation to CHD risk.


METHODS
We determined C242T genotype frequency in the P22(phox) gene and plasma levels of vitamin E in 565 Chinese patients with CHD and 609 control subjects. Logistic regression was used to control for potential confounders in multivariate analyses.


RESULTS
Compared with subjects with a CC genotype, subjects with a CT or TT genotype had a lower risk of CHD (multivariate-adjusted odds ratio [OR] 0.45, 95% CI 0.28-0.74, P = .001). Plasma concentrations of vitamin E were lower in case patients than in control subjects (multivariate-adjusted OR 0.65, 95% CI 0.50-0.86, P = .025). Compared with nonsmokers with a CC genotype, nonsmokers with a CT or TT genotype had a decreased risk of CHD (OR 0.25, 95% CI 0.12-0.53), but smokers with a CT or TT genotype had an increased risk (OR 2.04, 95% CI 0.74-5.61, P for interaction = .039). Smokers with a lower vitamin E concentration had a >3.0-fold greater risk of CHD than did nonsmokers with a higher vitamin E concentration (OR 3.52, 95% CI 2.36-5.24, P for interaction = .041).


CONCLUSIONS
These data provide evidence that P22(phox) genotypes are significantly associated with CHD risk in a Chinese population and suggest potential interactions among smoking, P22(phox) genotypes, and vitamin E in relation to CHD risk.
He
Mei-An
MA
Institute of Occupational Medicine and the Ministry of Education Key Lab of Environment and Health, Wuhan, Hubei, China.
Cheng
Long-Xian
LX
Jiang
Chang-Zheng
CZ
Zeng
He-Song
HS
Wang
Jing
J
Wang
Feng
F
Chen
Ying
Y
Yang
Miao
M
Tan
Hao
H
Zheng
Hong-Yan
HY
Hu
Frank B
FB
Wu
Tang-Chun
TC
D016022:Case-Control Studies; D002681:China; D003327:Coronary Disease / Q000097:blood* / Q000209:etiology / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D019255:NADPH Oxidases / Q000235:genetics*; D011110:Polymorphism, Genetic; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D014810:Vitamin E / Q000097:blood*
D014810:Vitamin E; D019255:NADPH Oxidases; C086986:CYBA protein, human