Genetic Study Links Increased Alcohol Consumption with Increased Risk of Stroke and PAD

Increased alcohol consumption has been shown to be associated with an increased risk of stroke or developing peripheral arterial disease, according to new research published today in Circulation: genomic and precision medicine, a magazine of the American Heart Association.

While observational studies have consistently shown that excessive alcohol consumption is associated with an increased risk of certain cardiovascular diseases, they often use self-reported data and cannot determine the cause. The researchers in this study used a different technique called Mendelian randomization that identifies genetic variants with a known association with potential risk factors to determine the potential degree of disease risk.

“Since genetic variants are determined at conception and cannot be affected by subsequent environmental factors, this technique allows us to better determine if a risk factor, in this case, excessive alcohol consumption, is the cause of a disease, or if it is simply associated “

said Susanna Larsson, Ph.D., principal investigator and associate professor of cardiovascular and nutritional epidemiology at the Karolinska Institute in Stockholm, Sweden. “To the best of our knowledge, this is the first Mendelian randomized study of alcohol use and various cardiovascular diseases.”

The researchers analyzed genetic data from several large-scale consortia and the UK Biobank, which tracks the health and well-being of 500,000 UK residents. The results indicate that with higher alcohol consumption:

• a threefold increase in peripheral arterial disease, a narrowing of the arteries resulting in reduced blood flow, usually to the legs;
• a 27% increase in the incidence of stroke; and
• some evidence of a positive association of coronary heart disease, atrial fibrillation, and aortic aneurysm.

“Increased alcohol consumption is a known cause of death and disability, however, it was previously unclear whether alcohol consumption is also a cause of cardiovascular disease. Given that many people regularly consume alcohol, it is important to untangle the risks or benefits, “said Larsson.

The researchers noted that this study suggested that the mechanism by which increased consumption is associated with the risk of stroke and PAD may be blood pressure.

According to a statement on diet health, the American Heart Association believes that alcohol consumption can be a component of a healthy diet if consumed in moderation (no more than one alcoholic beverage per day for women and 2 alcoholic beverages per day for men) and only for women and non-pregnant adults when there is no risk to existing health conditions, the interaction between drugs and alcohol, or personal safety and work situations. One drink equals 12 ounces of beer (5% alcohol); 5 ounces of wine (12% alcohol); or 1.5 ounces of 80 proof (40% alcohol) distilled spirits.

The study has some limitations. According to Dr. Larsson, the prevalence of heavy drinking in the UK Biobank was low, and the burden of increased cardiovascular disease risk is unlikely to be limited to heavy drinkers alone. Furthermore, the exact amount and frequency of alcohol consumed could not be quantified for this study. The researchers said the causal role of alcohol consumption in cardiovascular diseases other than stroke and peripheral arterial disease requires further investigation.