In recent years more careful consideration of epidemiological data has pointed to there being no health advantage to moderate alcohol consumption. Many past studies were looking at a form of alcohol consumption, such as moderate wine intake, that correlates with higher socioeconomic status. That in turn correlates with health and longevity, and the whole web of interlinked factors such as wealth, intelligence, education, and so forth.
The study here suggests another issue, in that groups who do not drink alcohol may have a higher proportion of people with risk factors for poor health and shorter life span than is the case in the general population. For example, people with a history of substance abuse, who do not drink at all as a necessary part of maintaining control over their lives. If one matches people who do not drink versus people who drink moderately, and ensure that other risk factors are the same on both sides, then the apparent advantage to drinking vanishes.
This is perhaps a similar situation to that arising in the epidemiology of excess fat tissue. Studies were showing a survival advantage to being moderately overweight in late life. That, however, is because the population of people who are thin at a given time in later life includes a sizable number who lost weight due to continuing ill health, and are thus at a higher risk of mortality going forward. People who remain thin throughout life have a survival advantage over their moderately overweight peers. There are many such cautionary tales in epidemiology regarding the interpretation of data.
Evidence suggests that people who abstain from alcohol have a higher mortality rate than those who drink low to moderate amounts. However, little is known about factors that might be causal for this finding. The objective was to analyze former alcohol or drug use disorders, risky drinking, tobacco smoking, and fair to poor health among persons who reported abstinence from alcohol drinking in the last 12 months before baseline in relation to total, cardiovascular, and cancer mortality 20 years later. A sample of residents aged 18 to 64 years had been drawn at random among the general population in northern Germany and a standardized interview conducted in the years 1996 to 1997. The baseline assessment included 4,093 persons (70.2% of those who had been eligible). Vital status and death certificate data were retrieved in the years 2017 and 2018.
We found that among the alcohol-abstinent study participants at baseline (447), there were 405 (90.60%) former alcohol consumers. Of the abstainers, 322 (72.04%) had met one or more criteria for former alcohol or drug dependence or abuse, alcohol risky drinking, or had tried to cut down or to stop drinking, were daily smokers, or self-rated their health as fair to poor. Among the abstainers with one or more of these risk factors, 114 (35.40%) had an alcohol use disorder or risky alcohol consumption in their history. Another 161 (50.00%) did not have such an alcohol-related risk but were daily smokers. The 322 alcohol-abstinent study participants with one or more of the risk factors had a shorter time to death than those with low to moderate alcohol consumption.
The Cox proportional hazard ratio (HR) was 2.44 for persons who had one or more criteria for an alcohol or drug use disorder fulfilled in their history and after adjustment for age and sex. The 125 alcohol-abstinent persons without these risk factors (27.96% of the abstainers) did not show a statistically significant difference from low to moderate alcohol consumers in total, cardiovascular, and cancer mortality. Those who had stayed alcohol abstinent throughout their life before (42; 9.40% of the alcohol-abstinent study participants at baseline) had an HR 1.64 compared to low to moderate alcohol consumers after adjustment for age, sex, and tobacco smoking.
The majority of the alcohol abstainers at baseline were former alcohol consumers and had risk factors that increased the likelihood of early death. Former alcohol use disorders, risky alcohol drinking, ever having smoked tobacco daily, and fair to poor health were associated with early death among alcohol abstainers. Those without an obvious history of these risk factors had a life expectancy similar to that of low to moderate alcohol consumers. The findings speak against recommendations to drink alcohol for health reasons.