Chronic alcohol consumption induces liver fibrosis (scarring) by stimulating the fat-storing cells of the liver to differentiate into collagen-producing stellate cells. It is believed this leads to irreversible cirrhosis. Alcoholic liver fibrosis may occur indirectly through acetaldehyde-protein adducts that can enhance collagen synthesis by stellate cells in vitro. Products of lipid peroxidation also increase collagen synthesis which may lead to fibrosis. Although there are a variety of biomechanical mechanisms through which alcohol or alcohol-metabolites may cause liver damage, the problem is more complex. Hereditary variations in enzymes may explain why only a small proportion of alcoholics develop serious liver disease. Although generic variants, polymorphisms in alcohol dehydrogenase (ADH), CYP2E1 isozyme, and aldehyde dehydrogenase (ALDH) result in various rates of alcohol metabolism among different ethnic groups, no single alcohol dehydrogenase allele has been causally linked to alcoholic liver injury. Aldehyde dehydrogenase polymorphisms may also play a role in the development of alcoholic liver injury. ALDHY, an allele which is present in about half of all Chinese and Japanese, encodes an enzyme that Read more [...]

Cardiovascular disease is the leading cause of death among Americans, followed by cancer and stroke (USDHHS). The role of alcohol as both a risk factor and a potential protective factor for cardiovascular disease has been the focus of intense investigation for many years. The results are clear: alcohol has both deleterious and beneficial effects, but the conditions under which alcohol exerts these unusual behavior effects and the mechanisms involved are complex at best. Alcohol and Heart Disease Alcohol and Blood Pressure Stroke Risk There are two relevant forms of stroke: ischemic and hemorrhagic. Ischemic stroke occurs when a blood vessel in the brain is blocked. Hemorrhagic stroke occurs when a blood vessel in the brain ruptures. Alcohol-related hypertension, or high blood pressure, may increase the risk of both forms of stroke. Yet, in people with normal blood pressure, the risk of ischemic stroke may be decreased due to the apparent ability of alcohol to lessen damage to blood vessels due to lipid deposits and to reduce blood clotting. However, whereas alcohol’s anticlotting effects may decrease the risk of ischemic stroke, alcohol-induced hypertension may increase the risk of hemorrhagic stroke. Two relatively Read more [...]

It has been known for nearly eighty years that heavy drinking decreases longevity. Pearl noted that moderate drinkers lived longer than either abstainers or heavy drinkers. Over the life span, total alcohol consumption is inversely associated with heart damage. The deterioration of heart muscle, a condition known as alcoholic cardiomyopathy, is one of the most serious consequences of chronic heavy drinking. As cardiac cells deteriorate, the unique ability of these cells to contract is impaired. This is particularly significant in the heart’s left ventricle which pumps freshly oxygenated blood throughout the body. Compensatory mechanisms result in an enlarged heart, but any benefit from such cardiac hypertrophy is temporary. Eventually the heart is unable to meet the body’s demand for oxygen. Alcoholic cardiomyopathy is the most common cause of non-ischemic cardiomyopathy in Western societies and is a major source of heart failure and death. As with other diseases, women may also be more sensitive to the toxic effects of alcohol on the heart, even though women drink less, or report drinking less, than men. Possible Beneficial Effects of Alcohol on Coronary Heart Disease Several prospective studies have reported Read more [...]

There is a well-documented association between heavy alcohol consumption and hypertension. Heavy alcohol consumption elevates blood pressure and causes or exacerbates hypertension. It is estimated that one drink per day can chronically increase blood pressure one millimeter of mercury in middle-aged individuals, and even more in the elderly and people with preexisting hypertension. Controversy remains as to whether moderate alcohol consumption has any beneficial effects on blood pressure, but reducing alcohol intake may be one means of reducing blood pressure in people with hypertension. Despite the well-recognized association between alcohol and hypertension, the cellular mechanisms of alcohol’s effect on blood pressure are not well understood and are made confusing by the fact that, initially, drinking alcohol dilates blood vessels, which lowers blood pressure. Studies looking to explain how long-term, heavy alcohol consumption reverses this effect and leads to elevated blood pressure have generally concluded that this effect is due to the actions of alcohol on the autonomic nervous system. For example, heavy alcohol consumption has been associated with increased release of the stress hormones adrenaline and norepinephrine, Read more [...]