Genetic modification of the effect of alcohol consumption on CHD

[Genetic polymorphism for genes of alcohol dependence]

Alcohol dependence is a complex disorder which is influenced by physiological, psychological, environmental factors, individual inheritance and so on. Several candidate genes associated with alcohol dependence risk have been identified. The review focuses on several related genes that control alcohol metabolism such as alcohol dehydrogenase, aldehyde dehydrogenase, cytochrome P450 2E1 and regulate neurotransmission such as catechol-O-methyltransferase, dopamine receptors D2 and D4, and mu opioid receptor.

Alcohol and cardio-respiratory deaths in Chinese: a population-based case-control study of 32,462 older Hong Kong adults

BACKGROUND

In observational studies moderate alcohol use reduces cardio-respiratory mortality. However observational studies may be biased by many factors including residual confounding by unmeasured differences between moderate alcohol users and other groups or by changes in alcohol use with ill-health and aging. We used two different analytic strategies in an under-studied population, i.e. southern Chinese, to provide an assessment of the specific impact of moderate alcohol use on mortality from ischemic heart disease (IHD) and chronic obstructive pulmonary diseases (COPD).

METHODS

In a population-based case-control study of all adult deaths in Hong Kong Chinese in 1998, we used adjusted logistic regression to compare alcohol use in decedents aged > or = 60 years from IHD (2270) and COPD (1441) with 10,320 living and 9043 dead controls (all non-alcohol related deaths). We also examined whether the association of alcohol use with death from IHD or COPD varied with sex or smoking status.

RESULTS

Using living controls and adjusted for age, socio-economic status and lifestyle, occasional and moderate alcohol use were generally associated with lower mortality from IHD and COPD. However, using dead controls the protection of occasional and moderate alcohol use appeared to be limited to ever-smokers for IHD (odds ratio (OR) 0.58, 95% confidence interval (CI) 0.46 to 0.73 for moderate compared to never-use in ever-smokers, but OR 1.07, 95% CI 0.76 to 1.50 in never-smokers), and possibly to men for COPD. High alcohol use was associated with lower IHD mortality and possibly with lower COPD mortality.

CONCLUSION

High levels of alcohol use in an older Chinese population were associated with lower IHD mortality. Moderate alcohol use was less consistently protective against IHD mortality. Alcohol use was associated with lower COPD mortality particularly in men, either due to some yet to be clarified properties of alcohol or as the artefactual result of genetic selection into alcohol use in a Chinese population. Given the increasing use of alcohol in China with economic development, other designs and analytic strategies are needed to assess the impact of alcohol in this population, so that an evidence-based public health policy can be formulated.

Relationship of alcohol consumption and type of alcoholic beverage consumed with plasma lipid levels: differences between Whites and African Americans of the ARIC study

PURPOSE

Alcohol consumption has been shown to contribute to a favorable lipid profile, and most studies have reported a reduction in coronary heart disease risk with low-to-moderate consumption of alcohol that is generally attributed to the beneficial effects of alcohol on lipids. The influence of different types of alcoholic beverages on plasma lipid levels has been investigated to a lesser extent and in limited populations.

METHODS

We investigated the effect of overall alcohol consumption, as well as the type of alcoholic beverage consumed, on multiple lipid measures in the large bi-ethnic population of the Atherosclerosis Risk in Communities study.

RESULTS

We found both low-to-moderate and heavy alcohol consumption, regardless of the type of alcoholic beverage consumed, to result in significantly greater levels of high-density lipoprotein (HDL) cholesterol, HDL3 cholesterol, and apolipoprotein A-I in both white and African-American males and females. Associations with other lipid measures contrasted between whites and African Americans, with greater levels of alcohol consumption resulting in significantly greater triglyceride levels in African Americans.

CONCLUSIONS

Our results confirm previous studies associating alcohol consumption, regardless of beverage type, with greater HDL cholesterol levels, with additional consistent associations detected for the major HDL cholesterol density subfraction, HDL3 cholesterol, and the major HDL cholesterol structural apolipoprotein, apolipoprotein A-I.

Alcohol dehydrogenase type 1C (ADH1C) variants, alcohol consumption traits, HDL-cholesterol and risk of coronary heart disease in women and men: British Women's Heart and Health Study and Caerphilly cohorts

The alcohol dehydrogenase 1C gene (ADH1C) gamma2gamma2 variant reportedly interacts with moderate alcohol consumption to increase HDL-cholesterol levels and reduce coronary heart disease (CHD). We undertook replication studies in two large population cohorts of women and men. 3234 women and 1313 men with relevant genotypic and phenotypic data from two prospective population cohorts were genotyped for ADH1C variants. No association was found between ADH1C variants and HDL-cholesterol, blood pressure or incident CHD, although ADH1C was associated with alcohol consumption. There was no evidence of interactions between ADH1C variants and moderate alcohol intake on HDL-cholesterol, blood pressure or CHD incidence. Life-long women abstainers had adverse risk factor profiles. Our findings do not support the hypothesis that ADH1C variants are associated with CHD risk in people who drink moderately.

Joint effects of eNOS gene T-786C and ADH2 Arg47His polymorphisms on the risk of premature coronary artery disease

INTRODUCTION

Both T-786C mutation in endothelial nitric oxide synthase (eNOS) gene and alcohol dehydrogenase (ADH) gene polymorphism such as ADH3 gamma1/gamma2 have been reportedly associated with coronary artery disease (CAD). Since ADH2 Arg47His polymorphism is common in Asian population, the aim of this present study was to assess the interaction between eNOS gene T-786C and ADH2 Arg47His polymorphisms on premature CAD risk.

MATERIALS AND METHODS

Hospital-based case-control study was conducted with 167 premature CAD and 235 late-onset CAD patients. Polymerase chain reaction restriction fragment length polymorphism was used to detect the polymorphisms. Multivariate logistic regression model was performed to adjust the potential confounders and estimate odds ratios (ORs) with 95% confidence intervals (CIs). Synergy index (S) was the measure to assess the interaction as departure from additivity.

RESULTS

After the adjustment for the potential confounders, and compared with the carriers of TT and Arg/Arg as the reference, the ORs with 95% CIs in parentheses of premature CAD were that 1.13 (0.19-6.59) for CT or CC and Arg/Arg carriers; 2.24 (0.77-6.49) for TT and Arg/His or His/His carriers; 4.18 (1.32-13.22) for CT or CC and Arg/His or His/His carriers, respectively. Based on those ORs, S was 2.32 (95% CI: 0.37-14.72).

CONCLUSIONS

The mutant genotypes of eNOS gene T-786C mutation and the fast form of ADH2 Arg47His polymorphism had an additive interaction on the risk of premature CAD in Chinese population. Further investigations with big sample size are necessary for confirming this additive interaction.

Alcohol use, vascular disease, and lipid-lowering drugs

Many epidemiological and clinical studies have shown that light-to-moderate alcohol (Alc) consumption is associated with reduced risk of coronary heart disease (CHD) and total mortality in middle-aged and elderly men and women. The plausible mechanisms for the putative cardioprotective effects include increased levels of high-density lipoprotein cholesterol, prevention of clot formation, reduced platelet aggregation, promotion of blood clot dissolution, and lowering of plasma lipoprotein (a) concentration. Individuals who need to be treated with lipid-lowering drugs, such as dyslipidemic or CHD patients, may benefit from these effects of Alc. Because hypolipidemic treatment is usually continued for life, an important issue is the suitability of Alc consumption in these patients. In the present review, the beneficial effects of Alc consumption on CHD risk, its side effects, and its safety and suitability when coadministered with hypolipidemic drugs are discussed.