And, once again, light-to-moderate consumption appears protective while heavy and binge drinking increase risk for myriad diseases.
But for light tippling only
Light-to-moderate drinking was once again associated with reduced odds of mortality in a large U.S. retrospective analysis, researchers found, recovering the protective effect of alcohol consumption that was challenged by other recent studies.
Compared with those who had fewer than 12 drinks in their life, light drinkers had lower mortality rates on multivariable adjustment (HR 0.79, 95% CI 0.76-0.82), as did moderate drinkers (HR 0.78, 95% CI 0.74-0.82). In particular, these two groups also had fewer cardiovascular-related deaths:
âº Light drinkers: HR 0.74 (95% CI 0.69-0.80)
âº Moderate drinkers: HR 0.71 (95% CI 0.64-0.78)
However, heavy drinkers were associated with higher mortality (HR 1.11, 95% CI 1.04-1.19) and cancer mortality specifically (HR 1.27, 95% CI 1.13-1.42). Once-a-week binges -- wherein one has five or more alcohol drinks in 1 day -- were also tied to more all-cause (HR 1.13, 95% CI 1.04-1.23) and cancer mortality (HR 1.22, 95% CI 1.05-1.41), according to Bo Xi, MD, of Shandong University in Shandong, China, and colleagues in the Journal of the American College of Cardiology.
"Using a large sample of U.S. adults, our study re-emphasized the existence of a J-shaped curve in the alcohol-mortality association, supporting current findings that light to moderate drinking might be protective, especially for cardiovascular disease, but heavy drinking or binge drinking has serious health consequences, including death," they concluded.
To overcome several methodological issues of previous studies -- including those that seemed to refute the protective effects of light-to-moderate drinking -- Xi's group used lifetime abstainers as the referent category in the present study to address abstainer bias. In addition, they adjusted for confounders such as demographic variables, lifestyle factors, and physician-diagnosed diseases.
"The number of people involved in their study was impressive, the methodology sound (inclusion of only lifetime abstainers in the reference group), and the statistical approach correct and supported by important ancillary analyses," wrote Giovanni de Gaetano, MD, PhD, and Simona Costanzo, PhD, both of IRCCS Istituto Neurologico Mediterraneo NEUROMED in Italy, in an accompanying editorial.
Even so, de Gaetano and Costanzo maintained, "a controlled, randomized, long-term trial is highly desirable and appears to be feasible."
What they took away from the study is that, for now, "for light-to-moderate levels of alcohol consumption, the risks of some cancers (breast, colorectal, oral) are relatively small and should be considered in the context of each individual global risk."
"Lifelong alcohol abstainers should not start drinking for health reasons only, but should be encouraged to adopt healthy lifestyles (regular physical activity, no smoking, weight control, and dietary habits such as the Mediterranean diet)," they added.
Xi's group linked National Health Interview Surveys (1997-2009) with National Death Index records up to 2011 for their study. They sampled 13 groups, ultimately including 333,247 adults in their analysis.
The investigators relied on self-reported alcohol consumption (participants categorizing themselves as lifetime abstainers, lifetime infrequent drinkers, former drinkers, current light, moderate, or heavy drinkers), which they acknowledged as a weakness that exposed the analysis to recall bias.
Other caveats: the possibility of changing drinking patterns throughout time, residual confounders despite multivariable adjustment, and the lack of data on type of alcohol consumed. Numerous baseline differences (such as smoking pattern) also existed across groups.
Over a median 8.2 years of follow-up, there were 34,754 deaths from cardiovascular disease (n=8,947) and cancer (n=8,427).
'The protective effect of light or moderate drinking on all-cause and cause-specific mortality was more pronounced in older adults (≥60 years of age) than in middle-aged adults (40 to 59 years of age). However, there was no significant association in young adults (18 to 39 years of age)," according to Xi's group. However, that may be because of the low number of outcomes in this demographic.
The study was supported by the Young Scholars Program of Shandong University.
Xi and co-authors, as well as de Gaetano and Costanzo, disclosed no relevant relationships with industry.
Reviewed by Henry A. Solomon, MD, FACP, FACC Clinical Associate Professor, Weill Cornell Medical College and Dorothy Caputo, MA, BSN, RN, Nurse Planner
last updated 08.14.2017
This article was first published on MedPage Today and reprinted with permission from UBM Medica. Free registration is required.