Extreme Alcohol Intake Directly Damages the Heart, Study Confirms

New data out of northwest Russia support the hypothesis that extremely heavy drinking can cause direct damage to the heart’s structure and function.

For the study, researchers led by Olena Iakunchykova, MS (UiT The Arctic University of Norway, Tromsø), sought to assess changes in cardiac biomarkers—specifically, N-terminal pro-B-type natriuretic peptide (NT-proBNP), high-sensitivity C-reactive protein (hsCRP), and high-sensitivity cardiac troponin T (hs-cTnT)—by focusing on alcohol consumption among people residing in the city of Arkhangelsk.

Most of the published work on cardiac biomarkers and alcohol involves moderate drinking, they point out in their paper published online recently in the Journal of the American Heart Association. By contrast, Iakunchykova and colleagues observe, “Russia is one of the countries that has had a tradition of heavy drinking of spirits and has been characterized as having a particularly harmful drinking profile.”

Kenneth Mukamal, MD (Beth Israel Deaconess Medical Center, Boston, MA), commenting on the results for TCTMD, said, “There’s not a lot that’s new here [but] what’s interesting is just the unusual population. This is a part of Russia that’s not normally very well studied and tends to have very high rates of binge drinking, . . . at a minimum hazardous and potentially worse beyond that.”

That said, Mukamal added, it’s useful to see that the study confirms previous reports suggesting a link between alcohol and cardiac damage.

The Harms

Iakunchykova et al analyzed data on 2,354 participants from the general population, dividing them into three categories: those who drank no alcohol, those who consumed alcohol but didn’t experience the signs of heavy/harmful drinking, and heavy drinkers who met the criteria for harmful drinking. Additionally, the researchers looked at 271 individuals being treated for alcohol problems at a local psychiatric hospital.

Examples of heavy/harmful drinking included, among other things, feeling hungover or sleeping in clothes at night due to drunkenness, failing family or personal obligations due to alcohol, binge drinking, and needing to drink first thing in the morning.

After adjustment for potential confounders, harmful drinkers had 30.1% higher NT-proBNP and 28.4% higher hsCRP levels than did people who engaged in “nonproblem drinking.” Heavy drinking that didn’t reach the level of “harmful” was not tied to any significant difference in these biomarkers. The subgroup of individuals from the narcology clinic, in comparison, had 34.9% higher NT-proBNP, 99.7% higher hsCRP, and 10.3% higher hs-cTnT levels than did the nonproblem-drinking group.

“Overall, NT-proBNP and hsCRP increased with increasing intensity of alcohol exposure,” the researchers note, reporting a P for trend value of < 0.001. “These results support the hypothesis that heavy alcohol drinking has an adverse effect on cardiac structure and function that may not be driven by atherosclerosis,” they conclude.

As for how to generalize the findings, Mukamal said “there’s no reason to think that what they’re observing here wouldn’t apply to equally heavy [drinkers] elsewhere,” with the caveat, though, that “these are pretty serious drinkers.”

In the nonproblem group, for example, one out of every 20 people said they binge drink at least once a month, he pointed out. “Even their lightest-drinking folks are still consuming a lot, at least periodically.”

Alcohol has long been known to weaken the heart muscle beyond the atherosclerotic process that occurs in blood vessels, he noted. In the study participants being treated for alcohol problems, the hs-cTnT indicates ongoing subclinical damage and the NT-proBNP suggests strain on the heart.

Less clear, said Mukamal, is whether the observed inflammation in some way mediates the hs-cTnT and NT-proBNP levels and whether treating the inflammation might prevent cardiac damage. However, it’s commonly been assumed that inflammation is secondary to the organ damage caused by alcohol, he commented.