Tuesday, 07 November 2017 16:16

In contrast to excessive consumption, light to moderate consumption of wine/alcoholic beverages can lower risk of heart failure and may not cause atrial fibrillation

In this prospective study of a Mediterranean population (more than 22,800 men and women), moderate drinkers compared to abstainer, had a lower risk of heart failure. Wine was the preferred alcoholic beverage.

Heart failure (HF), often referred to as congestive heart failure, occurs when the heart is unable to pump sufficiently to maintain the blood flow in order to meet the body's needs. The problem can originate from damage or overloading. 

Common causes of HF include high blood pressure, atrial fibrillation (*), valvular heart disease, infection, and cardiomyopathy (**) or a previous heart attack. Another common cause is excess use of alcoholic beverages. HF causes shortness of breath which usually becomes worse with exercise, and while lying down, and may wake the person at night. Typical symptoms of HF also include excessive tiredness, a limited ability to exercise, and leg swelling. Chest pain, as in angina, does not typically occur due to heart failure.

Initially, the heart tries to make up for the failure by enlarging: it stretches to contract more strongly and keep up with the demand to pump more blood. Because the contracting cells of the heart get bigger, an increase in muscle mass occurs, which initially allows the heart to pump more strongly. At the same time, the heart will be pumping faster to increase its output. In addition, the body compensates for HF by narrowing the blood vessels to increase the blood pressure, trying to make up for the heart's loss of power. Also, the body diverts blood away from less important tissues and organs to the heart and brain. While these temporary measures initially mask the problem, HF untreated usually continues and worsens until these substitute processes fail and becomes a life-threatening condition.

Studies have shown that excessive consumption of alcoholic beverages increases the risk of HF and atrial fibrillation (AF), however, the effect of light-moderate alcohol intake is less certain. Di Castelnuovo and colleagues (Italy) aimed to assess among participants of the MOLI-Sani study, if and what amounts of alcohol consumption are associated with the onset of HF and/or AF. They followed 22,824 AF- or HF-free subjects (48% men, age ≥35 years) for approx. 8.2 years. During the follow-up period, a total of 943 cases of HF and 554 of AF were identified. In comparison to never drinkers, ingesting 1 to 4 alcoholic drinks/day (wine was the prevailing alcoholic beverage in this population) was associated with a lower risk of HF, with a 22% maximum risk reduction at 20 g/day, independent of common confounding variables. They also found that both former and occasional drinkers showed a comparable risk of developing HF as never drinkers.

The authors, however, observed no association with the consumption of alcoholic beverages and the onset of AF.

Another group of scientists recently looked at this relationship in a Norwegian population-based HUNT study. They investigated the association between alcohol consumption within recommended limits and AF risk in a light-drinking population. During the 8-year follow-up period, 1697 out of the 47,002 participants were diagnosed with AF. The risk increased in a curvilinear manner, with a threshold at which AF risk clearly increased above that of nondrinkers at about 4 to 5 drinks per week. The risk for AF increased significantly by 38 % in participants consuming more than 7 drinks per week compared to abstainers. The scientists concluded that the attributable risk of moderate alcohol consumption within recommended limits among participants without binge or problem drinking was negligible in this population.

 

(*) Atrial fibrillation (AF) is an irregular, often very fast heartbeat (arrhythmia) that can lead to blood clots, stroke, heart failure and other heart-related complications. Normally, the heart contracts and relaxes to a regular beat. In atrial fibrillation, the upper chambers of the heart beat irregularly instead of beating effectively to move blood into the ventricles.

(**) Cardiomyopathy is a diseased heart muscle that cannot contract adequately.

When the heart fails to contract properly, oxygenated blood is not pumped adequately to the tissues and organs of the body. This inability to deliver oxygen to body tissues can lead to a general weakness and fatigue. Other symptoms may include shortness of breath on exertion or chest pain.

 

Di Castelnuovo A, Costanzo S, Bonaccio M et al. Moderate Alcohol Consumption Is Associated With Lower Risk for Heart Failure But Not Atrial Fibrillation. JACC Heart Fail. 2017 Oct 4. [Epub ahead of print]

For more information about this article, read the scientific abstract here.

 

Usually, a standard drink contains 10 g of ethanol, which is the equivalent of approx. 100 ml of wine. However, the definitions of a standard drink and of moderate drinking are not the same in every study. At the end of every study, the respective definitions are specified.

12 g/day of ethanol = 1 alcoholic drink

Drinking categories were defined as:

Former drinkers, abstainers, occasional drinkers: up to 1g/day or equivalently 2.5 alcoholic drinks/month

>1 g to 12g of ethanol/day

>12g to 24g of ethanol/day

>24g to 48g of ethanol/d

> 48 g of ethanol /d

Irregular drinkers: > 48g of ethanol/d (4 alcoholic drinks) for women and > 5 alcoholic drinks/d for men

 

Gémes K, Malmo V, Laugsand LE, et al. Does Moderate Drinking Increase the Risk of Atrial Fibrillation? The Norwegian HUNT (Nord-Trøndelag Health) Study.
Drinking within recommended limits:

1 Standard drink = 12 g of ethanol

Non-risky drinking: Up to 1 drink/day for women and up to 2 drinks/d for men

Disclaimer

The authors have taken reasonable care in ensuring the accuracy of the information herein at the time of publication and are not responsible for any errors or omissions. Read more on our disclaimer.