Editorial: From MACH15 to MACH0 – a missed opportunity to understand the health effects of moderate alcohol intake

A burden of proof study on alcohol consumption and ischemic heart disease

Cohort and case-control data have suggested an association between low to moderate alcohol consumption and decreased risk of ischemic heart disease (IHD), yet results from Mendelian randomization (MR) studies designed to reduce bias have shown either no or a harmful association. Here we conducted an updated systematic review and re-evaluated existing cohort, case-control, and MR data using the burden of proof meta-analytical framework. Cohort and case-control data show low to moderate alcohol consumption is associated with decreased IHD risk - specifically, intake is inversely related to IHD and myocardial infarction morbidity in both sexes and IHD mortality in males - while pooled MR data show no association, confirming that self-reported versus genetically predicted alcohol use data yield conflicting findings about the alcohol-IHD relationship. Our results highlight the need to advance MR methodologies and emulate randomized trials using large observational databases to obtain more definitive answers to this critical public health question.

Principles of engagement on research and other collaborations between the brewing sector and research entities: the FACT Principles

Public-private partnerships are subject to intense scrutiny. This is specifically the case for sensitive health-related topics such as alcohol consumption. The brewing sector and representatives of the scientific community therefore stressed the need for specific principles for the proper and transparent governance of research and other collaborations between the brewing sector and research entities. At a 1-day seminar, a group of scientists and representatives from the brewing and food sector reached a consensus for such principles. They adhere to the following four fundamental conditions: Freedom of research, Accessibility, Contextualisation and Transparency. The points of focus in the FACT principles are open science, meaning that the methods and results are made accessible and reusable, and relationships are clearly disclosed. Actions to be taken for dissemination and implementation of the FACT Principles are, for instance, publishing them on public websites, including them in formal research agreements, and citing them in scientific publications. Scientific journals and (research) societies are encouraged to support the FACT Principles. In conclusion, the FACT Principles provide a framework for increased transparency and control of funding-related bias in research and other collaborations between the brewing sector and research entities. Monitoring their use and evaluating their impact will help to further refine and enforce the FACT Principles in the future.

Alcohol, Drinking Pattern, and Chronic Disease

This review discusses the inconsistent recommendations on alcohol consumption and its association with chronic disease, highlighting the need for an evidence-based consensus. Alcohol is an addictive substance consumed worldwide, especially in European countries. Recommendations on alcohol consumption are controversial. On one hand, many nonrandomized studies defend that moderate consumption has a beneficial cardiovascular effect or a lower risk of all-cause mortality. On the other hand, alcohol is associated with an increased risk of cancer, neurological diseases, or injuries, among others. For years, efforts have been made to answer the question regarding the safe amount of alcohol intake, but controversies remain. Observational studies advocate moderate alcohol consumption following a Mediterranean pattern (red wine with meals avoiding binge drinking) as the best option for current drinkers. However, agencies such as the IARC recommend abstention from alcohol as it is a potent carcinogen. In this context, more randomized trial with larger sample size and hard clinical endpoints should be conducted to clarify the available evidence and provide clinicians with support for their clinical practice.

Alcohol consumption in relation to cardiovascular diseases and mortality: a systematic review of Mendelian randomization studies

The causal effects of alcohol-in-moderation on cardiometabolic health are continuously debated. Mendelian randomization (MR) is an established method to address causal questions in observational studies. We performed a systematic review of the current evidence from MR studies on the association between alcohol consumption and cardiometabolic diseases, all-cause mortality and cardiovascular risk factors. We performed a systematic search of the literature, including search terms on type of design and exposure. We assessed methodological quality based on key elements of the MR design: use of a full instrumental variable analysis and validation of the three key MR assumptions. We additionally looked at exploration of non-linearity. We reported the direction of the studied associations. Our search yielded 24 studies that were eligible for inclusion. A full instrumental variable analysis was performed in 17 studies (71%) and 13 out of 24 studies (54%) validated all three key assumptions. Five studies (21%) assessed potential non-linearity. In general, null associations were reported for genetically predicted alcohol consumption with the primary outcomes cardiovascular disease (67%) and diabetes (75%), while the only study on all-cause mortality reported a detrimental association. Considering the heterogeneity in methodological quality of the included MR studies, it is not yet possible to draw conclusions on the causal role of moderate alcohol consumption on cardiometabolic health. As MR is a rapidly evolving field, we expect that future MR studies, especially with recent developments regarding instrument selection and non-linearity methodology, will further substantiate this discussion.

Alcohol type and ideal cardiovascular health among adults of the Multi-Ethnic Study of Atherosclerosis

BACKGROUND

Light to moderate alcohol consumption is associated with favorable cardiovascular health (CVH). However, the association between alcohol type and ideal CVH has not been well-established. We examined the relationship between alcohol type and ideal CVH as measured by the American Heart Association's seven CVH metrics.

METHODS

We analyzed data from 6,389 men and women aged 45-84 years from a multi-ethnic cohort free of cardiovascular disease. Alcohol type (wine, beer and liquor) was categorized as never, former, 0 but drink other alcohol types, >0 but <1 drink/day, 1-2 drinks/day and >2 drinks/day. A CVH score ranging from 0 to 14 points was created from the seven CVH metrics (Inadequate score, 0-8; average, 9-10; optimal, 11-14). We used multinomial logistic regression to examine the association between alcohol type and CVH, adjusting for age, sex, race/ethnicity, education, income, health insurance, field site and total calorie intake.

RESULTS

The mean (SD) age of participants was 62 (10) years and 53 % were women. Participants who consumed 1-2 drinks/day of wine had higher odds of optimal CVH scores compared to those who never drank wine [adjusted prevalence odds ratio (POR) 1.64 (1.12-2.40)]. In comparison to participants who never drank beer, those who consumed >2 drinks/day of beer had lower odds of optimal CVH scores [0.31 (0.14-0.69)]. Additionally, those who consumed >2 drinks/day of liquor had lower odds of optimal scores compared to those who never drank liquor [0.32 (0.16-0.65)].

CONCLUSION

Moderate consumption of wine was associated with favorable CVH. However, heavy consumption of beer or liquor was associated with poorer CVH.