Immediate vs prolonged cardiovascular effects of moderate consumption of alcoholic beverages

In an attempt to evaluate the immediate and long-term effects of alcohol intake, the current meta-analysis suggests that moderate drinking may be associated with an immediately higher risk of cardiovascular events, which disappears after 24 hours.

While moderate intake of alcoholic beverages has long-term cardiovascular benefits, it is less clear, whether it could pose an acute increased cardiovascular risk. Researchers from the Harvard University in the US carried out a systematic review and meta-analysis of observational studies to examine the association between intake of alcoholic beverages and cardiovascular events in the following hours and days. Immediately after consuming alcoholic beverages, the cardiovascular risk was higher (*), however, already 24 hours later, a lower risk of myocardial infarction and hemorrhagic stroke was observed; only heavy drinking (6-9 drinks/day) continued to confer a higher risk in the following hours and days . After one week, there was a lower risk of ischemic stroke, consistent with previous research showing cardiovascular benefits of moderate drinking.

(*) The following possible mechanisms for these associations are proposed: Immediately following alcohol intake, both harmful and protective physiological responses take place in the body. Within 1 to 3 hours, a single dose of alcohol increases heart rate and changes in blood clotting factors, however by 12 to 24 hours, an alcohol dose of the equivalent of 2 alcoholic beverages causes transient improvements in blood flow, endothelial function and blood clotting factors. Within weeks of regular intake, improvements in inflammatory markers, the lipid profile, and adipokines (cell signalizing protein secreted by the adipose tissue and involved in inflammation) and insulin sensitivity can be observed. Regular moderate consumption of alcoholic beverages (1–2 drinks per day) is associated with improved high-density lipoprotein cholesterol levels, heart rate variability, endothelial function, insulin sensitivity, reduced blood clotting, and a lower risk of cardiovascular disease and ischemic stroke and hemorrhagic stroke.

Mostofsky E, Chahal HS, Mukamal KJ, et al. Alcohol and Immediate Risk of Cardiovascular Events: A Systematic Review and Dose-Response Meta-Analysis. Circulation 2016;133(10):979-87.

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