To find the curious correlation, researchers at Washington University School of Medicine in St. Louis recently studied 5,974 Australian twins born between 1902 and 1964, along with their spouses. By looking at twins and their spouses, the researchers were able to compare and measure genetic and environmental influences related to alcoholism.
“We found that people at risk for alcohol dependence tend to marry others who are at risk," said Julia Grant, one of the study’s authors.
Although anyone can become an alcoholic, genetics account for about half of a person's risk, while the other half comes down to environmental variables—such as employment, interests, friends, family and one’s partner, Grant said.
Yet when researchers looked at the influence of one partner's alcoholic behavior, it tended to reduce the same in the other partner. In other words, when one spouse abuses alcohol, the other might actually reduce their alcohol intake.
"We don't really know how this works," she said. "It is possible that an individual decreases his or her alcohol consumption in reaction to the other's excessive alcohol use. Maybe one person is responsible for getting the kids up and out for school in the morning, for example."
The findings appear in a recent issue of the journal Alcoholism: Clinical & Experimental Research. Grant hopes to expand the study and see how spouses influence one another, in terms of risk of alcoholism as well as other disorders like depression.