Arrhythmias—Heavy drinking—and especially “binge” drinking—are associated with both atrial and ventricular arrhythmias. Patients undergoing alcohol withdrawal syndrome can develop severe arrhythmias that may reflect abnormalities of potassium or magnesium metabolism as well as enhanced release of catecholamines. Seizures, syncope, and sudden death during alcohol withdrawal may be due to these arrhythmias.
3.
Hypertension—A link between heavier alcohol consumption (more than three drinks per day) and hypertension has been firmly established in epidemiologic studies. Alcohol is estimated to be responsible for approximately 5% of cases of hypertension, independent of obesity, salt intake, coffee drinking, and cigarette smoking. A reduction in alcohol intake appears to be effective in lowering blood pressure in hypertensive individuals who are also heavy drinkers; the hypertension seen in this population is also responsive to standard blood pressure medications.
4.
Coronary heart disease—Although the deleterious effects of excessive alcohol use on the cardiovascular system are well established, there is strong epidemiologic evidence that moderate alcohol consumption actually prevents coronary heart disease (CHD), ischemic stroke, and peripheral arterial disease. This type of relationship between mortality and the dose of a drug is called a “J-shaped” relationship. Results of these clinical studies are supported by ethanol’s ability to raise serum levels of high-density lipoprotein (HDL) cholesterol (the form of cholesterol that appears to protect against atherosclerosis; see Chapter 35), by its ability to inhibit some of the inflammatory processes that underlie atherosclerosis while also increasing production of the endogenous anticoagulant tissue plasminogen activator (t-PA, see Chapter 34), and by the presence in alcoholic beverages (especially red wine) of antioxidants and other substances that may protect against atherosclerosis. These observational studies are intriguing, but randomized clinical trials examining the possible benefit of moderate alcohol consumption in prevention of CHD have not been carried out.
D. Blood
Alcohol indirectly affects hematopoiesis through metabolic and nutritional effects and may also directly inhibit the proliferation of all cellular elements in bone marrow. The most common hematologic disorder seen in chronic drinkers is mild anemia resulting from alcohol-related folic acid deficiency. Iron deficiency anemia may result from gastrointestinal bleeding. Alcohol has also been implicated as a cause of several hemolytic syndromes, some of which are associated with hyperlipidemia and severe liver disease.
E. Endocrine System and Electrolyte Balance
Chronic alcohol use has important effects on the endocrine system and on fluid and electrolyte balance. Clinical reports of gynecomastia and testicular atrophy in alcoholics with or without cirrhosis suggest a derangement in steroid hormone balance.
Individuals with chronic liver disease may have disorders of fluid and electrolyte balance, including ascites, edema, and effusions. Alterations of whole body potassium induced by vomiting and diarrhea, as well as severe secondary aldosteronism, may contribute to muscle weakness and can be worsened by diuretic therapy. The metabolic derangements caused by metabolism of large amounts of ethanol can result in hypoglycemia, as a result of impaired hepatic gluconeogenesis, and in ketosis, caused by excessive lipolytic factors, especially increased cortisol and growth hormone.
F. Fetal Alcohol Syndrome