Observational research has suggested that light alcohol consumption may have beneficial effects on heart health, but in a large study published in Open JAMA Network, alcohol consumption at all levels was associated with higher risks of cardiovascular disease. The findings, which are published by a team led by researchers from Massachusetts General Hospital (MGH) and the Broad Institute of MIT and Harvard, suggest that the supposed benefits of alcohol consumption may in fact be attributed to other lifestyle factors that are common between light and alcohol. moderate drinkers.
The study included 371,463 adults – with an average age of 57 and an average alcohol consumption of 9.2 drinks per week – who participated in the UK Biobank, a large-scale biomedical database and resource research containing in-depth genetic and health data. information. Consistent with previous studies, researchers found that light to moderate drinkers had the lowest risk of heart disease, followed by people who abstained from drinking. People who drank heavily had the highest risk. However, the team also found that light to moderate drinkers tended to have healthier lifestyles than abstainers – such as more physical activity and vegetable consumption, and less smoking. Consideration of a few lifestyle factors significantly reduces the benefits associated with alcohol consumption.
The study also applied the latest techniques in a method called Mendelian randomization, which uses genetic variants to determine whether an observed link between an exposure and an outcome is consistent with a causal effect – in this case, if light consumption of ‘alcohol causes a person to protect against cardiovascular disease. “Newer and more advanced techniques of ‘nonlinear Mendelian randomization’ now make it possible to use human genetic data to assess the direction and magnitude of disease risk associated with different levels of exposure,” says the lead author. Krishna G. Aragam, MD, MS, MGH Cardiologist and Broad Institute Research Fellow. “We therefore leveraged these new techniques and the extensive genetic and phenotypic data from the biobank populations to better understand the association between habitual alcohol consumption and cardiovascular disease.”
When scientists performed such genetic analyzes of samples taken from participants, they found that people with genetic variants that predicted higher alcohol consumption were indeed more likely to consume greater amounts of alcohol. and more likely to suffer from hypertension and coronary heart disease. The analyzes also revealed substantial differences in cardiovascular risk across the spectrum of alcohol consumption in men and women, with minimal increases in risk from zero to seven drinks per week, higher when going from seven to 14 drinks per week, and a particularly high risk when drinking 21 or more drinks per week. Notably, the results suggest an increased cardiovascular risk even at levels deemed “low risk” by the U.S. Department of Agriculture’s national guidelines (i.e., below two drinks per day for men and women). one drink a day for women).
The finding that the relationship between alcohol consumption and cardiovascular risk is not linear but rather exponential was supported by further analysis of data from 30,716 participants at the Mass General Brigham Biobank. Therefore, although reducing intake may benefit even people who drink one alcoholic beverage per day, the health benefits of reducing may be more substantial – and, perhaps, more clinically significant – in those who consume more.
“The results affirm that alcohol consumption should not be recommended for improving cardiovascular health; rather, reducing alcohol consumption is likely to reduce cardiovascular risk in all individuals, although to varying degrees depending on based on their current level of consumption,” says Aragam.
The study’s lead author was Kiran J. Biddinger, and other authors included Connor A. Emdin, MD, DPhil, Mary E. Haas, PhD, Minxian Wang, PhD, George Hindy, MD, Patrick T. Ellinor , MD, PhD, Sekar Kathiresan, MD, and Amit V. Khera, MD, MSc.
Funding was provided by the National Institutes of Health and the American Heart Association.