Researchers at the Yale School of Medicine think they have found a way to predict a recovering alcoholic’s chance of relapsing.

Their study, conducted with patients at the Connecticut Mental Health Center, was the first ever to show a correlation between an increased likelihood to fall into relapse and reduced gray matter in regions of the brain associated with impulse control. The American Journal of Psychiatry published the findings in February, and the article’s conclusions could soon have far-reaching implications for alcohol treatment, according to study director Rajita Sinha, a professor of psychiatry at the School of Medicine.

Sinha and her team studied patients who had undergone four weeks of alcohol abuse treatment at the health center. The researchers used magnetic resonance imaging to measure gray matter volumes, a reliable indicator of neural count and functionality, in various regions of patients’ brains. The researchers contacted the patients three times over the following 90 days, and they discovered that those who relapsed in a shorter period of time had possessed relatively less gray matter in certain areas of the brain when scanned before discharge.

The key area of the brain in predicting relapse rates was the prefrontal cortex, an area associated with impulse control and executive function.

Sinha, who also directs Yale’s Interdisciplinary Stress Center, said that patients with inhibited executive function often relapse because of the challenges they face upon leaving alcohol recovery treatment. Patients with a lower volume of gray matter in their impulse control centers might be predisposed to drink if presented an opportunity, she said.

“One can imagine that when one is faced with being in a bar or near a highly stressful situation the impulse to drink would likely be very high,” she said.

Since the study only imaged the patients’ brains while they were recovering from alcohol abuse, and not before or after their stay in the treatment center, it shed no light on the cause of the reduced gray matter, Sinha said. Even so, she blamed a number of factors for brain shrinkage, including genetic predisposition, stress and alcohol itself. Sinha’s lab recently submitted a similar paper for review that used functional magnetic resonance imaging to link weak levels of activity in parts of the brain’s prefrontal cortex to be associated with high alcohol craving.

Sinha’s peers said that one of the strengths of the study was the design that tracked patients after they finished inpatient treatment.

“[Sinha] is putting together a jigsaw puzzle of the factors that contribute to relapse,” said Markus Heilig, clinical director of the National Institute of Alcohol Abuse and Alcoholism, an organization that seeks to reduce alcohol-related problems. “I don’t think anybody has done it as well as she has done it, both in assessing people on the research unit and executing very impressive clinical follow up.”

The researchers’ conclusions are significant because they bring to a close decades of unconfirmed speculation about the correlation between gray matter and relapse proclivity, Edith Sullivan, a professor of psychiatry and behavioral sciences at the Stanford University School of Medicine, wrote in an email to the News.

If Sinha’s findings gain widespread acceptance, doctors could identify individuals at a greater risk of relapse and adjust behavioral and pharmacological treatment appropriately. One of the most exciting potential therapies to counter gray matter loss is neurogenesis, the use of pharmaceuticals to restore brain volume, but Heilig said its development is “a very long shot.”

“I’m not sure I can come up with any drugs to alter the functioning of the frontal lobe,” he said.

While the high cost of brain scanning technology could prevent the widespread implementation of this technique in clinics, Heilig said there are alternate methods, such as psychological tests, to evaluate the functionality of the prefrontal cortex without directly measuring its volume.

About 70 percent of the patients in this study relapsed within 60 days of treatment discharge.