Alcohol Intake in Patients With Cardiomyopathy and Heart Failure: Consensus and Controversy.

Alcohol is often cited to be a common cause of cardiomyopathy and heart failure. However, in most available population-based studies, a modest-to-moderate alcohol consumption has been associated with favorable effects on the cardiovascular system, including a lowered risk of heart failure, compared with no alcohol consumption. Available genetic epidemiological data have not supported a causal association between alcohol consumption and heart failure risk, suggesting that alcohol may not be a common cause of heart failure in the community. Data linking alcohol intake with cardiomyopathy risk are sparse, and the concept of alcoholic cardiomyopathy stems mainly from case series of selected patients with dilated cardiomyopathy, where a large proportion reported a history of excessive alcohol intake. This state-of-the-art paper addresses the current knowledge of the epidemiology of alcoholic cardiomyopathy and the role of alcohol intake in patients with non-alcohol-related heart failure. It also offers directions to future research in the area. The review questions the validity of current clinical teaching in the area. It is not well known how much alcohol is needed to cause disease, and the epidemiological pathways linking alcohol consumption to cardiomyopathy and heart failure are not well understood. Until more evidence becomes available, caution is warranted before labeling patients as having alcoholic cardiomyopathy due to a risk of neglecting other contributors, such as genetic causes of cardiomyopathy. In non-alcohol-related heart failure, it is unknown whether total abstinence is improving outcomes (compared with moderate drinking). Ideally, randomized clinical trials are needed to answer this question.