Does Moderate Alcohol Consumption Have a Role in Cardiovascular Disease Prevention?

Alcohol Consumption and Cardiovascular Disease

Alcohol has long been demonstrated to have toxic effects on the human body, but in recent years clinical data suggest that alcohol consumption may actually confer cardiovascular (CV) health benefits.¹

The risk-benefit relationship observed between alcohol and CV health may be expressed as a U-shaped curve. Observational data point to better CV outcomes — which encompass CV morbidity and mortality — in people who drink moderate amounts of alcohol compared with nondrinkers. Overall CV health may be improved in moderate drinkers as well.² On the other hand, heavy alcohol intake clearly increases the risk for coronary artery disease, stroke, and death.¹

However, whether such a U-shaped curve truly exists has been called into question. “The majority of previous studies have typically looked at whether different levels of alcohol consumption are associated with a higher or lower risk of developing any type of cardiovascular disease,” Steven Bell, PhD, from the University of Cambridge in the United Kingdom, said in an interview with Cardiology Advisor. “However, there are lots of different types of cardiovascular disease, with distinct underlying biology, so it is not necessarily so that alcohol would affect risk of developing them all in the same way.”

“Grouping together disorders may therefore obscure subtle differences that may be present across diseases. This is important because it is often cited that drinking a small amount of alcohol may be ‘good for your heart,’ but if this relationship is driven by a handful of diseases, and there is no difference or even an elevated risk for a variety of other disorders, then we are not communicating the full picture so that people can make a better-informed decision about their level of alcohol intake.”

In addition, the nondrinking groups that have been studied were often heterogeneous and included occasional drinkers, former drinkers, and never drinkers. Former drinkers have worse CV outcomes than never drinkers, and their inclusion in the nondrinking groups may have diluted any potential benefits associated with lifelong abstention from alcohol.²

A Population-Based Study on Alcohol and Cardiovascular Disease

In an attempt to clarify some of issues associated with prior studies, Dr Bell and colleagues conducted a large, population-based cohort study evaluating the relationship between alcohol intake and several cardiovascular diseases (CVDs) that are known to arise from different pathophysiological processes.²

A total of 114,859 individuals with an incident CVD diagnosis were identified from linked electronic health record data. Drinking status was classified as follows: nondrinker, occasional drinker, former drinker, current moderate drinker, and heavy drinker.²

Evaluation of the outcomes for aggregated CVD (eg, all-cause death, coronary heart disease, CVD, and fatal CVD end points) demonstrated a J-shaped relationship, with moderate drinkers at lower risk for adverse outcomes than nondrinkers, former drinkers, and heavy drinkers.²

The risk for developing specific CV phenotypes was assessed using moderate drinkers as the standard for comparison. Nondrinkers, occasional drinkers, former drinkers, and heavy drinkers had higher rates of unheralded coronary death, heart failure, and peripheral arterial disease as their first CVD. However, heavy drinkers were less likely to have incident myocardial infarction (hazard ratio [HR], 0.88) and stable angina (HR, 0.93) than moderate drinkers.²

Nondrinkers were also more likely than moderate drinkers to experience myocardial infarction (HR, 1.32), ischemic stroke (HR, 1.12), and abdominal aortic aneurysm (HR, 1.32). Heavy drinkers were at higher risk for cardiac arrest (HR, 1.50) and intracranial hemorrhage (HR, 1.37) compared with moderate drinkers.²