Cardioprotective effects of light-moderate consumption of alcohol: a review of putative mechanisms.

There is abundant epidemiological and clinical evidence showing that light-moderate drinking is associated with a reduced risk of coronary heart disease (CHD), total and ischaemic stroke and total mortality in middle-aged and elderly men and women. The epidemiological evidence suggests a J- or U-shaped relationship between alcohol and CHD. However, the apparent benefits of moderate drinking on CHD mortality are offset at higher drinking levels by increasing risk of death from other types of heart diseases (cardiomyopathy, arrhythmia etc.), neurological disorders, cancer, liver cirrhosis, and traffic accidents. The plausible mechanisms for the putative cardioprotective effects include increased levels of high-density lipoprotein cholesterol, decreased levels of low-density lipoprotein cholesterol, prevention of clot formation, reduction in platelet aggregation, and lowering of plasma apolipoprotein(a) concentration. Thus, alcohol reduces the risk of coronary vascular diseases both by inhibiting the formation of atheroma and decreasing the rate of blood coagulation.

Apolipoprotein E polymorphism in Northern Indian patients with coronary heart disease: phenotype distribution and relation to serum lipids and lipoproteins.

Apolipoprotein E (apo E), a genetic determinant of plasma lipid levels and coronary heart disease (CHD) needs to be investigated in Asian Indians since they have a propensity to develop dyslipidemia and accelerated atherosclerosis. We studied apo E phenotypes and plasma lipid levels in 52 Northern Indian male patients (aged 38-71 years) with angiographically proven CHD, and compared them to 50 healthy blood donors taken as the control group. High levels of Lp(a), (p < 0.05), and a definite trend towards lower levels of HDL-C (p < 0.05), was observed in the CHD patients as compared to the control subjects. The frequency of apo E allele epsilon3 was 0.86 and 0.862, and epsilon4 allele was 0.12 and 0.08 in the patients and controls, respectively. However, a lower frequency of the E2 allele was observed in the patient group (E2 = 0.02) as compared to the controls (epsilon2 = 0.06) (p = ns). In individuals with apo E3/E3 phenotype, significantly lower HDL-C levels was observed in the CHD patients as compared to the control subjects (p < 0.05). A positive correlation was observed between apo E phenotypes and Lp(a) levels in the CHD subjects as compared to the controls (p < 0.05), the level being significantly high in CHD subjects with at least one E4 allele. To conclude, in this sample of Northern Indian subjects with CHD, there is a significant correlation between apo E3/E3 phenotype and low levels of HDL-C as compared to the control subjects. Further, apo E phenotype is positively correlated with high Lp(a) levels in the CHD subjects having at least one E4 allele. However, these relationships need to be explored in a larger sample of subjects.