What is the relationship between average daily alcohol consumption and all-cause mortality?

A recent study published in the journal JAMA network open, Researchers investigated the association between alcohol consumption and the risk of all-cause mortality, and the role of bias in influencing outcomes.

study: Association between daily alcohol intake and all-cause mortality risk. Image Credit: dan.nikonov/Shutterstock.com

Background

The proposition that low-level alcohol consumption may provide health benefits and prevent death from all causes is highly controversial.

Observational studies and various meta-analyses have reported that people who drink moderate amounts of alcohol live longer and are less likely to develop heart disease than those who abstain.

However, there is evidence that these findings are the result of systematic biases, such as the use of health indicators unrelated to alcohol consumption, such as diet, dental hygiene, income, and weight.

Other prejudices include the inability to distinguish between complete abstainers and former drinkers, and that abstainers may have poor health from other causes.

Two previous meta-analyses by the same team of researchers found that low levels of alcohol consumption were not associated with a reduced risk of death when potential confounding variables and biases were considered.

However, the authors believe that the emergence of newer, more recent studies warrants reexamining this association.

About research

In the current study, researchers conducted a systematic review of studies published up to July 2021 and performed a meta-analysis to determine the association between alcohol consumption and all-cause mortality risk.

In addition, this analysis also investigated the association between all-cause mortality risk and alcohol consumption according to the median age and gender distribution of the study population.

To minimize the bias associated with lifetime selection, the researchers studied a cohort consisting of individuals recruited before age 51 and were followed to a minimum median age of 60. .

To eliminate the ill-health bias associated with alcohol abstainers, the analysis included occasional drinkers, i.e., drinkers less than once a week, as comparisons.

Data from studies included in the systematic review, including measures of alcohol consumption, all-cause mortality outcomes, cohort age during recruitment and follow-up, control variables, and types of errors, including misclassification of abstainers and consumers. was extracted. for meta-analysis.

result

They reported that low-level alcohol consumption (less than 25 g per day) was not associated with a lower risk of all-cause mortality in both sexes. However, the risk of all-cause mortality was significantly higher in women who consumed 25g or more of alcohol per day and men who consumed 45g or more of alcohol per day.

After accounting for potential biases and confounding effects, including sampling and misclassification of ex-drinkers, we did not find that low alcohol consumption confers protective benefits, such as reduced risk of all-cause mortality.

A systematic review found that the error of misclassifying former or occasional drinkers as sober is very common, with 86 of the 107 studies making such errors. .

The study also found that biases in the classification of abstainers and other study features altered the relationship between all-cause mortality risk and alcohol consumption, and that most studies contrasted the potential protective effects of low-dose alcohol consumption. and increased alcohol risk. alcohol consumption.

Furthermore, using occasional drinkers as a reference group reported a significant protective effect of low-level alcohol use, but a non-significant protective effect of low-level alcohol consumption compared to using non-drinkers as a reference group. was also obtained.

Not only did individuals who consumed 45 g or more of alcohol per day have an increased risk of death in a fully adjusted meta-analysis model, but the risk of female drinkers was significantly higher than that of female abstainers. it was high.

Conclusion

In summary, the researchers determined, through a systematic review of studies published up to July 2021 and a meta-analysis of data from these studies, to establish an association between light alcohol consumption and reduced risk of all-cause mortality. I investigated.

Overall, the findings showed that low-level alcohol consumption does not provide a protective effect against all-cause mortality risk when all biases and potential confounding factors are considered.

Furthermore, the results showed that women who drank more than 25 g of alcohol per day had a significantly higher risk of death than women who did not drink, while men who drank more than 45 g of alcohol per day had an increased risk of death. .