“A vexing question has been whether usual intake of small amounts of alcohol is associated with a higher level of BP. We identified a continuous, more or less linear association, with no evidence of a threshold for the association,” study coauthor Paul Whelton, MD, of Tulane University School of Public Health and Tropical Medicine, New Orleans, said in an interview.
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For systolic BP (SBP), “the most important BP risk indicator for CVD [cardiovascular disease], the association was robust, being present in both men and women and in both North America as well as Asia,” Dr. Whelton noted.
Based on the results, “the lower the better, and no consumption even better, as we did not find any indication that human health may benefit from consumption of very small amounts of alcohol,” senior author Marco Vinceti, MD, PhD, of University of Modena and Reggio Emilia University in Italy, told this news organization.
“Clearly, alcohol is not the only or necessarily the main determinant of high blood pressure, and the effects of small intakes of alcohol emerging from our pooled analysis were certainly not biologically as relevant and meaningful as those induced by high intakes,” Dr. Vinceti added.
The study was published online in Hypertension.
The researchers analyzed data from seven large, observational studies conducted in the United States, Korea, and Japan involving 19,548 adults (65% men).
Participants ranged in age from 20 years to the early 70s at baseline and were followed for a median of 5.3 years (range, 4-12 years). None of the participants had previously been diagnosed with hypertension or other CVD, diabetes, liver disease, alcoholism, or binge drinking.
Compared with nondrinkers, SBP was 1.25 mm Hg higher in adults who consumed an average of 12 grams of alcohol per day, rising to 4.90 mm Hg in adults consuming an average of 48 grams of alcohol per day.
For reference, in the United States, 12 ounces of regular beer, 5 ounces of wine, or a 1.5-ounce shot of distilled spirits contains about 14 grams of alcohol.
Diastolic BP (DBP) was 1.14 mm Hg higher in adults who consumed an average of 12 grams of alcohol per day, rising to 3.10 mm Hg in those who consumed an average of 48 grams of alcohol per day.
Subgroup analyses by gender showed an almost linear association between baseline alcohol intake and SBP changes in men and women and for DBP in men, while in women, there was an inverted U-shaped association.
No safe level
“From a BP perspective, it’s best to avoid alcohol intake. This is what the WHO [World Health Organization] recommends,” Dr. Whelton said.
“If someone is already drinking alcohol and does not want to stop doing so, minimizing alcohol consumption is desirable; many guidelines recommend not starting to drink alcohol but in those already drinking alcohol, consumption of two or less standard drinks per day for men and one or less standard drinks of alcohol per day for women,” Dr. Whelton noted.
Commenting on the study for this article, Alberto Ascherio, MD, of Harvard T. H. Chan School of Public Health, Boston, said it’s been known for more than 30 years that alcohol intake is associated with increased systolic and diastolic BP. The added value of this new study is a “refinement of the estimate of the dose response.”
Dr. Ascherio noted that “moderate alcohol consumption is associated with a modest increase in risk of cancer, but, in spite of the adverse association with BP, with a potentially beneficial effect on cardiovascular disease.” However, “the causality of the latter association has been questioned, but there is no consensus on this.”
Also weighing in, Timothy Brennan, MD, MPH, chief of clinical services for the Addiction Institute of Mount Sinai Health System in New York City, said this new study represents “yet another piece of evidence suggesting that there simply is no ‘healthy’ amount of alcohol use in humans.
“Even small amounts of alcohol intake can have negative health effects, as demonstrated in this study,” Dr. Brennan said. “There is still a widely held belief among people that drinking in moderation is good for you. It is becoming more and more clear that this is simply not the case. As health authorities grapple with drinking ‘recommendations,’ additional datasets like these will be helpful.”
The study had no specific funding. Dr. Whelton, Dr. Vinceti, Dr. Ascherio, and Dr. Brennan have no relevant disclosures.
A version of this article first appeared on Medscape.com.