Link between alcohol consumption and cardiovascular death depends on socioeconomics

Very frequent consumption of alcohol is associated with an increased risk of dying from cardiovascular disease, but only among people in the lowest socioeconomic position, according to a new research study published in PLOS Medicine by Eirik Degerud from the Norwegian Institute of Public Health in Oslo, and colleagues.

Individuals with low socioeconomic position are known to consume alcohol less frequently than those in higher positions, but experience a higher rate of alcohol-related hospitalizations and deaths. Degerud and colleagues analyzed socioeconomic and health survey data, as well as cause of death information, on 207,394 Norwegian adults who were born before October 15, 1960 and completed mandatory censuses in Norway between 1960 and 1990.

Moderately frequent alcohol consumers (2-3 times per week) had a lower risk of dying from cardiovascular disease than infrequent drinkers, and this association was more pronounced among people in the highest socioeconomic position. Very frequent consumption of alcohol (4-7 times per week) was associated with an increased risk of dying from cardiovascular disease among people in the lowest socioeconomic position. The authors also report that weekly binge drinkers had higher risk of dying from cardiovascular disease than those who did not binge drink in the past year, but the risk did not seem to differ by socioeconomic position.

"It is unclear if [these difference in risk] reflects differential confounding of alcohol consumption with health-protective or damaging exposures or differing effects of alcohol on health across socioeconomic groups," the authors say. "The heterogeneity between groups in the population needs to be assessed when making population recommendations regarding alcohol consumption."

In an accompanying Perspective, Jurgen Rehm and Charlotte Probst of Canada's Centre for Addiction and Mental Health write that the new findings are an important piece of the puzzle in understanding the complex interactions between socioeconomic position and mortality. An implication of the new paper, they say, is that "it is not appropriate simply to extrapolate from risks associated with alcohol use in higher-income populations to address lower-income populations where the impact of alcohol use is highest."