Alcohol Consumption and Cardiovascular Disease: How much is too much?

Most enjoy sipping on a glass of wine, a beer, or cocktail from time to time on their own, or with a group of others. And in more of these occasions than not, the individual determines how much he or she could or could drink given future plans (e.g. driving a vehicle).

But, why don’t people consider the impact a drink of alcohol consumption could have on their health more?

This is likely because of the recommendations of drinking alcohol in moderation. Alcohol has been shown to have protective effects regarding how we use our fats in our blood (3). There is even data that shows a reduction in the incidence of heart attacks related to alcohol consumption (4).

In 2019, about 26%  of people ages 18 and older (29.7 percent of men in this age group and 22.2 percent of women in this age group) reported that they engaged in binge drinking in the past month (1). Binge drinking is 5 or more drinks for men and 4 or more drinks for women in about 2 hours (2). The Dietary Guidelines of 2020-2025 define Alcoholic beverages as the following:

“Adults of legal drinking age can choose not to drink, or to drink in moderation by limiting intake to 2 drinks or less in a day for men and 1 drink or less in a day for women, when alcohol is consumed. Drinking less is better for health than drinking more.”

It is important to define what one alcoholic drink equivalent. About 14 grams (0.6 fl oz) of pure alcohol is one drink, 12 fluid ounces of regular beer (5% alcohol), 5 fluid ounces of wine (12% alcohol), or 1.5 fluid ounces of 80 proof distilled spirits (40% alcohol) (2).

Most importantly, what is a moderate amount of alcohol consumption?

A moderate amount is 2 drinks of less a day for men and 1 drink of less a day for women. Okay, what if we drink alcohol above the defined moderation?

Well, the National Institute on Alcohol Abuse and Alcoholism reported that people who drank alcohol two times the gender-specific binge drinking thresholds were 70 times more likely to have an alcohol-related visit to the emergency department. Furthermore, those who consumed alcohol at three times the gender-specific binge thresholds were 93 times more likely to have an emergency department visit.

Perception of a lot and little:

How good are we in determining moderation? In a 2015, a cross-sectionally analysis from the eHeart Health Study dataset had participants answer the following questions (5):

Do you believe alcohol is good for your heart?” – “Yes,”“No,”or“I don’t know.”

You believe alcohol is good for your heart because?” –“ Your doctor told you,” “You learned this in school,” “You learned from reading lay press,” “You learned this from friends, colleagues, or word of mouth, ”or “Other [free text]. Over 5,000 people answered the questions and approximately 30% felt alcohol consumption was health healthy, 39% felt it was unhealthy and 31% were unsure. The majority of the perceptions were related to information retained from the lay press.

The lay press giving us some health guidance! Shocking, I know.

More importantly, it is important to determine the causal effects we see in observational studies. Those are studies that conclude “x” amount of alcohol is related or associated “y” outcome of health. So researchers design studies termed “Mendelian Randomization”. The study looks at genes known to function to look at modifiable (lifestyle) exposure to disease. Larsson et al. published a Mendelian Randomization study in 2020 that investigated the effect of alcohol consumption on 8 cardiovascular diseases (6). The authors found that high alcohol consumption may be causally associated with an increased risk of stroke and peripheral artery disease. Furthermore, the link may occur through blood pressure changes.

Blood pressure changes are controlled by our nervous system. A recent study from Greenlund et al. investigated the effects of night binge alcohol consumption on sleep, morning-after blood pressure, and muscle sympathetic activity (7).  Twelve men and ten women were included in this randomized cross-over design. The alcohol had a 1:3 ratio of 95% ethanol mixed orange or cranberry juice. Sounds pretty yummy. The alcohol dose was a 1 g/kg dose for men and a 0.85 g/kg dose for women.. The authors utilize the Valsalva maneuver to observe the changes in blood pressure after the night of binge drinking.  The Valsalva maneuver leads to a decrease in heart rate and blood pressure, which then stimulates the sympathetic nervous system and allowing the investigators to examine changes in sympathetic function.

There were increases in resting heart rate the next morning, but blood pressure remained unchanged compared to the fluid control condition. During the Valsalva maneuver, there was a heightened sympathoexcitatory response and a reduced baroreflex response. Furthermore, a night of binge drinking disrupted sleep quality (reduced REM sleep).

Studies that use Mendelian randomization, or have a practical approach of viewing the morning effect effects have significant roles in improving the comprehension of the information received from the lay news. Alcohol consumption is certainly linked with cardiovascular disease. The idea of everything in moderation seems to prevail. However, the amount that is perceived to be a lot person to person varies, making alcohol consumption a known risk to health. People’s perceptions of themselves could change the amount of alcohol consumed in one sitting, which could increase the risk of binge drinking (8).

References

1. Alcohol Facts and Statistics | National Institute on Alcohol Abuse and Alcoholism (NIAAA) [Internet]. [cited 2021 Mar 14]. Available from: https://www.niaaa.nih.gov/publications/brochures-and-fact-sheets/alcohol-facts-and-statistics
2. Dietary Guidelines for Americans, 2020-2025 and Online Materials | Dietary Guidelines for Americans [Internet]. [cited 2021 Mar 14]. Available from: https://www.dietaryguidelines.gov/resources/2020-2025-dietary-guidelines-online-materials
3. Gaziano JM, Buring JE, Breslow JL, Goldhaber SZ, Rosner B, Vandenburgh M, et al. Moderate Alcohol Intake, Increased Levels of High-Density Lipoprotein and Its Subfractions, and Decreased Risk of Myocardial Infarction. New England Journal of Medicine. 1993;329(25):1829–34.
4. Camargo Jr. CA, Stampfer MJ, Glynn RJ, Grodstein F, Gaziano JM, Manson JE, et al. Moderate Alcohol Consumption and Risk for Angina Pectoris or Myocardial Infarction in U.S. Male Physicians. Ann Intern Med. 1997 Mar 1;126(5):372–5.
5. Whitman IR, Pletcher MJ, Vittinghoff E, Imburgia KE, Maguire C, Bettencourt L, et al. Perceptions, Information Sources, and Behavior Regarding Alcohol and Heart Health. The American Journal of Cardiology. 2015 Aug 15;116(4):642–6.
6. Larsson Susanna C., Burgess Stephen, Mason Amy M., Michaëlsson Karl. Alcohol Consumption and Cardiovascular Disease. Circulation: Genomic and Precision Medicine. 2020 Jun 1;13(3):e002814.
7. Greenlund IM, Cunningham HA, Tikkanen AL, Bigalke JA, Smoot CA, Durocher JJ, et al. Morning sympathetic activity after evening binge alcohol consumption. Am J Physiol Heart Circ Physiol. 2021 Jan 1;320(1):H305–15.
8. Cromer JR, Cromer JA, Maruff P, Snyder PJ. Perception of alcohol intoxication shows acute tolerance while executive functions remain impaired. Experimental and Clinical Psychopharmacology. 2010;18(4):329–39.

“The views, opinions and positions expressed within this blog are those of the author(s) alone and do not represent those of the American Heart Association. The accuracy, completeness and validity of any statements made within this article are not guaranteed. We accept no liability for any errors, omissions or representations. The copyright of this content belongs to the author and any liability with regards to infringement of intellectual property rights remains with them. The Early Career Voice blog is not intended to provide medical advice or treatment. Only your healthcare provider can provide that. The American Heart Association recommends that you consult your healthcare provider regarding your personal health matters. If you think you are having a heart attack, stroke or another emergency, please call 911 immediately.”