June 12, 2023

expert reaction to study of light-to-moderate alcohol consumption and heart health

A study published in Journal of American College of Cardiology looks at the effect of alcohol on cardiovascular risk.

Dr Sadie Boniface, Head of Research at the Institute of Alcohol Studies and Visiting Researcher, King’s College London, said:

“This study used brain scans to explore a potential mechanism behind associations between moderate alcohol use and cardiovascular disease, and the press release matches the paper.

“Similar to many other studies, the non-drinker group had several worse health and socio-economic indicators at the start of the study. For example, the ‘none/minimal’ drinkers reported higher rates of hypertension, diabetes, anxiety and depression; getting less exercise; and lower levels of education, employment, and income than the ‘light/moderate’ drinkers. The paper says these potential confounders were addressed in further supplementary analyses, along with other analyses addressing biases in how categories of drinkers are defined (note – I have not seen these, so cannot comment).

“There are many health different effects of alcohol. In this study, higher rates of cancers were noted among moderate drinkers, and poorer cognitive health was also seen among people with higher levels of alcohol use. This fits with what we know from other studies. For example, recent evidence from a major systematic review shows that occasional or moderate alcohol use does not protect against mortality from all causes. Indeed, the authors recommend interventions to improve heart health around reducing stress, rather than reaching for alcohol.”

Prof Petra Meier, Professor of Public Health, University of Glasgow, said:

“Many studies show that light to moderate drinkers are at lower risk of disease compared to abstainers, and this is not limited to heart disease. There are a number of explanations including that light-to-moderate drinkers are different from abstainers in relation to a number of personal characteristics. These differences explain why low-level alcohol consumption appears to be associated with beneficial health outcomes, but without alcohol consumption being the causative factor. Two well-documented examples are 1. Socio-demographic differences, for example, ethnic minority groups have higher rates of abstention for religious and cultural reasons and, causally unrelated, also have poorer health outcomes. 2. So-called “sick-quitters” – people with health problems/who are on certain medications often used to drink, sometimes heavily, but quit alcohol consumption in response to their medical conditions (so here we have is reverse causation – it is not abstention causing them to be less healthy but being less healthy causes abstention after lifetime heavy consumption). The study was able to include some of these factors but not comprehensively – for example, neither lifetime alcohol consumption history nor ethnicity were included.”

Prof Naveed Sattar, Professor of Metabolic Medicine, University of Glasgow, said:

“This complex paper tries to work out why moderate alcohol may be associated with lower heart attack risks.  The issue is we know any amount of alcohol is associated with more strokes and heart failure, and with increases in cancer and deaths from cardiovascular causes.

“So to concentrate only on one small aspect, even if true, gives the wrong impression and the title of better heart health with light to moderate alcohol is misleading and perpetuates old myths we really need to move on from.”   

‘Reduced Stress-Related Neural Network Activity Mediates the Effect of Alcohol on Cardiovascular Risk’ by Kenechukwu Mezue et al. was published in Journal of American College of Cardiology at 19:00 UK time on Monday 12^th June.

DOI: https://doi.org/10.1016/j.jacc.2023.04.015

Declared interests

Dr Sadie Boniface: “I work at the Institute of Alcohol Studies which receives funding from the Alliance House Foundation.”

Prof Petra Meier: “no interests to declare”

Prof Naveed Sattar: “teetotaller and, as chair of SIGN cardiovascular prevention 2017 guidelines, we recommended the following “Patients with or without evidence of cardiovascular disease should be advised to reduce alcohol consumption and that even light to moderate alcohol consumption may increase cardiovascular risk.”