Low-volume drinking does not protect against death from all causes: JAMA

"We found no significant protective associations of occasional or low-volume drinking (moderate drinking) with death from all causes," the authors wrote. "An increased risk of all-cause mortality was seen for drinkers who consumed 25 g or more and a significantly elevated risk when drinking 45 g or more per day."

A prior meta-analysis of the association between alcohol use and death from all causes revealed no statistically significant decrease in mortality risk at low consumption levels compared with lifetime nondrinkers. However, the risk estimates may be impacted by the number and quality of available studies, particularly for women and younger cohorts. Jinhui Zhao from the University of Victoria, Victoria, British Columbia in Canada, and colleagues aimed to investigate the association between alcohol intake and all-cause mortality and how sources of bias may modify the results.

For this purpose, the researchers systematically searched online databases to identify studies published between 1980 and 2021. The review recognized 107 studies of alcohol use and mortality from all causes. Relative risks were modelled using mixed linear regression models, first pooled for all studies and then stratified by sex (females versus males) and median cohort age ( ≥56 years versus <56)

The study's primary outcome was the relative risk estimates for the association between mean daily alcohol consumption and all-cause mortality.

The study led to the following findings:

• For the analysis, there were 724 risk estimates of all-cause mortality due to alcohol consumption from the 107 cohort studies (4 838-825 participants and 425 564 deaths available).
• In models adjusting for former drinker bias, potential confounding effects of sampling variation, and other prespecified study-level quality criteria, the meta-analysis of all 107 included studies showed no remarkably lowered risk of all-cause mortality in low volume or occasional (>0 to <1.3 g of ethanol per day) drinkers (1.3-24.0 g per day) versus lifetime nondrinkers.
• In the fully adjusted model, there was a nonsignificantly elevated risk of all-cause mortality in drinkers who consumed 25 to 44 g per day (RR, 1.05) and significantly increased risk for drinkers who consumed 45-64 and 65 or more grams per day (RR, 1.19 and 1.35).
• Female drinkers had significantly more significant mortality risks than female lifetime nondrinkers (RR, 1.22).

To conclude, the updated meta-analysis did not find a significantly lower risk of all-cause mortality linked with low-volume alcohol consumption.

"Future longitudinal studies in this field will be needed to minimize lifetime selection biases by not including occasional and former drinkers in the reference group and by using younger cohorts at baseline," the authors concluded.

Reference:

Zhao J, Stockwell T, Naimi T, Churchill S, Clay J, Sherk A. Association Between Daily Alcohol Intake and Risk of All-Cause Mortality: A Systematic Review and Meta-analyses. JAMA Netw Open. 2023;6(3):e236185. doi:10.1001/jamanetworkopen.2023.6185