Background: Binge drinking (the consumption of large quantities (>5 units) of alcohol in a short period) is associated with increased cardiovascular mortality. Wine polyphenols are considered to be protective against cardiovascular diseases. We conducted an experimental study to evaluate the acute effects of alcohol consumption on flow-mediated vasodilation and general cardiovascular parameters, using beverages with high polyphenolic content (HPC) and low polyphenolic content (LPC).
Methods: Two groups of ten volunteers were asked to drink two different kinds of beverages. in 45 minutes, three units of red wine or an alcoholic beverage with a low polyphenolic count were consumed. Then 45 minutes were allowed for complete uptake of the alcohol or polyphenolic compounds. Next, all volunteers underwent blood pressure readings, ECG and flow-mediated vasodilation. Blood samples were taken at the same time for routine chemistry, inflammation parameters and lipids. Then the entire cycle was repeated once (in total six units of alcohol in 180 minutes).
Results: No differences were found between the two drinks. Alcohol itself dose-dependently increased forearm blood flow by vasodilation of both arterioles and distribution arteries. However, flow-mediated vasodilation (FMD) for the LPC group (n=10) decreased from 7.31 +/- 4.78 (% +/- sd) to 2.82 +/- 2.9 after three drinks and 1.21 +/- 3.25 after six drinks. The FMD values for the HPC group (n=10) decreased from 8.61 +/- 1.78 to 1.78 +/- 3.71 and 1.19 +/- 2.6. There were no significant changes between the LPC and the LPC group at the three time points.
Conclusion: Although ethanol produces vasodilation at the level of the distribution artery as well as at an arteriolar level, it causes a decrease in flow-mediated vasodilation. This endothelial dysfunction is not corrected by the polyphenols present in wine.