A study conducted by the Yale School of Medicine has found that states with smoking bans in bars may also have higher recovery rates from alcohol use disorder, or AUD.

Past data have shown that smokers are four times as likely as non-smokers to have AUD, and approximately 35 percent of individuals with AUD are nicotine-dependent. However, the Yale study was the first in the country to observe the relationship between smoking bans in bars and AUD remission rates. The study’s findings were published in the journal “Drug and Alcohol Dependence” in late September.

Using information collected by the National Epidemiological Survey on Alcohol and Related Conditions, researchers analyzed data that surveyed 19,763 citizens in 49 states from 2001-’02 and 2004-’05. Almost 85 percent of the study’s participants came from states that do not have smoke-free bar policies. The other 15 percent came from the eight states in the country that do — Delaware, Connecticut, Maine, Massachusetts, New York, Rhode Island, Vermont and Washington.

“Smoking and drinking are considered complements, so if smoking becomes more difficult, use of alcohol may decline,” said Jody Sindelar, one of the study’s lead authors and a professor at both the Yale School of Public Health and Yale School of Medicine. “This would be likely to occur in bars in which smoking is banned.”

Professor Kurt Ribisl of the University of North Carolina Gillings School of Public Health said the findings were intriguing. Smoking bans, he said, were originally created to decrease tobacco smoke in public places and private establishments, but this finding adds a new boon to a long-fought public health campaign.

Yet policy recommendations related to smoking bans in bars may not necessarily result from this study.

“This is not a strong enough study, with strong enough results linked to causality, for which you could make [a policy] recommendation and not be faced with a lot of criticism,” said Adam Goldstein, Professor at the UNC School of Medicine and Director of the UNC Nicotine Dependence Program.

Location-specific smoking bans, Goldstein added, may not necessarily lead to an overall decrease in smoking — only smoking in those locations. This principle may extend to alcohol consumption as well, he said.

In order to prove causality between bar smoking bans and AUD, Goldstein said, experiments would need to eliminate existing differences in factors besides the presence or absence of a smoking ban. Both Goldstein and Ribisl said states with smoking bans in bars tend to focus more on public health and may already have strong campaigns focusing on AUD.

Although causality has yet to be proven, Ribisl added that studies establishing relationships usually occur before those determining causality.

“It’s the natural evolution of research,” he said.

The study was funded primarily by the National Institutes of Health.