The health benefits of including a moderate amount of alcohol in the diet have been vigorously debated in research. Now, a new study finds that drinking up to seven drinks a week is linked to a lower risk of developing heart failure in the future.
Heart failure – a major public health problem experienced by 23 million people worldwide – is characterized by the heart being less able to pump blood around the body than it has previously. This impaired pumping ability usually happens when the heart muscle has been damaged from a heart attack. The following are contributory factors for the development of heart failure:
- High blood pressure
- Heart muscle disease (cardiomyopathy)
- Heart valve problems
- An irregular heart beat (arrhythmia)
- Viral infections
- Drinking excessive amounts of alcohol
- Consuming recreational drugs
- Side-effects of radiotherapy treatment for cancer.
In a new study published in the European Heart Journal, researchers from Brigham and Women’s Hospital in Boston, MA, analyzed data from the Atherosclerosis Risk in Communities Study, which included 14,629 participants aged between 45 and 64 years. The participants were recruited between 1987 and 1989 and they were followed for 24-25 years.
Interviews were conducted with the participants on their drinking habits at the start of the study and at follow-up interviews conducted at 3-yearly intervals.
From this data, the researchers divided the participants into the following categories:
For the purposes of the study, one “drink” was defined as a beverage containing 14 g of alcohol, approximately equivalent to a small (125 ml) glass of wine, just over half a pint of beer or less than one shot of liquor.
Over the course of the study, 1,271 male participants and 1,237 female participants developed heart failure. The lowest rate of heart failure in the study was among participants who consumed up to seven drinks per week and the highest rate was among those who were former drinkers.
The researchers calculated that men who consumed up to seven drinks a week had a 20% lower risk of developing heart failure compared to abstainers, and women consuming the same amount had a 16% lower risk.
The study found former drinkers to have the highest risk of developing heart failure – 19% increased risk among men and 17% among women, compared with abstainers.
Although it might be expected that the highest risk for developing heart failure would be among the heaviest drinkers in the study, the researchers found that participants who drank 14 or more drinks per week did not have a significantly different risk of heart failure to that of the abstainers.
The researchers suggest that this result may be due to the study featuring a small number of participants who were very heavy drinkers, so the association may not have been fully detected. However, the authors did find an association between drinking 21 or more drinks a week and increased risk of death from all causes for 47% of men and 89% of women.
When calculating risk, the authors took into account various confounding factors, including age, diabetes, high blood pressure, heart disease or heart attacks, body mass index (BMI), cholesterol levels, physical activity and education and smoking.
The researchers note that the protective effects of moderate drinking are less pronounced in women than in men. They hypothesize that this may be due to the differences between how men and women metabolize alcohol.
“These findings suggest that drinking alcohol in moderation does not contribute to an increased risk of heart failure and may even be protective,” says co-author Dr. Scott Solomon, senior physician at Brigham and Women’s Hospital. “No level of alcohol intake was associated with a higher risk of heart failure. However, heavy alcohol use is certainly a risk factor for deaths from any cause.”