(Reuters Health) - Getting more exercise throughout life is tied to a reduced risk of abusing alcohol that requires treatment, according to a new study from Denmark.

In a group of adults followed for 20 years, those who reported being more active in their free time were less likely to need hospitalization or treatment for an alcohol use disorder, but the direction and explanation for the relationship is unclear.

“Although we and for that matter others have not proven a causal relationship between physical activity and risk of developing alcohol use disorders, it is likely that there is a causal link,” said Dr. Ulrik Becker of the National Institute of Public Health at the University of Southern Denmark in Copenhagen, coauthor of the new report.

“We know from other studies that physical activity reduces the risk of other psychiatric problems . . . as well as studies that seem to show that physical activity increases the benefit of treatment in alcohol use disorder patients,” Becker told Reuters Health by email.

Researchers used data from a series of four surveys mailed to more than 18,000 adults in Copenhagen between 1976 and 2003, including questions about their leisure time physical activity, medications, alcohol use and smoking.

The researchers divided respondents into three groups based on leisure-time activity level: high levels of activity (more than four hours per week), low levels (two to four hours per week), and sedentary. About half of the respondents reported high levels of activity throughout the study. In 1976, 20 percent reported being sedentary, which decreased to 10 percent in 2001.

The researchers linked these questionnaire responses to national patient registries of all people given outpatient treatment or admitted to a hospital for an alcohol use disorder in Denmark through 2011.

By the end of the study, 736 people, or four percent of the original group, had been diagnosed with an alcohol use disorder. People who reported low or high levels of leisure time activity had similar risks for an alcohol use disorder, but people in the sedentary group had a higher risk, the authors write in Alcohol and Alcoholism.

Men and women who reported at least low levels of physical activity were 30 to 40 percent less likely to be diagnosed with an alcohol use disorder than those in the sedentary group.

Activity at work was not associated with alcohol use disorders, the authors write.

“These results strengthen the general recommendation of increased physical activity and add to the long list of beneficial effects of physical activity,” Becker said.

Likely more than half of what determines alcohol use disorders is genetic, but environmental factors, like physical activity, are also important, he said.

“It’s an interesting observational study and demonstrates there’s some correlation,” said Michael T. French, who was not part of the new study but directs the Health Economics Research Group at the University of Miami.

French studied a large group of U.S. adults in 2009 and found that heavier drinkers tended to exercise more, which does not align with the new results.

“Like the study of ours, the most you can say is that there seems to be an association,” French told Reuters Health by phone. Their findings may have differed because French’s study included a range of alcohol use, whereas Becker’s study was limited to the most extreme drinkers who ended up hospitalized, he said.

“They are hypothesizing that less physical activity or a sedentary lifestyle is going to affect your risk of an alcohol use disorder,” French said. “It’s equally possible that acquiring a disorder is going to lead to a sedentary lifestyle.”

“They decided they’re going to look at physical activity as predictors, but we thought it was more plausible to look in the other direction,” he said.

French stressed that at this point, trying to explain why activity influences alcohol disorders, or vice versa, is only conjecture.

“It’s an interesting topic, worth exploring, but I would be cautious when interpreting the results,” he said.

SOURCE: http://bit.ly/1FvDo1v Alcohol and Alcoholism, online December 27, 2014.

(By Kathryn Doyle)