Predicting stubborn alcohol addiction: mood, motive may hold keys

By Melissa Healy

7:20 PM EDT, May 2, 2013


It doesn't take stacks of research to demonstrate that medicating painful feelings with alcohol or drugs is a dangerous and ultimately futile strategy (although those studies do exist). But the relationship between emotional difficulties and alcohol addiction has always been a complex one, in a chicken-and-egg way: does alcohol -- a depressive agent -- make people who use it become depressed? Or are depressed people more likely to drink heavily to self-medicate, and then to become dependent on alcohol?

Two new studies explore the links between mood and alcoholism in an effort to predict who becomes alcohol-dependent and which alcoholics are most likely to relapse.

One of those studies -- published online this week by the journal JAMA Psychiatry -- uses brain scanners to help tease out a possible "biomarker" for the most stubborn forms of alcoholism, and finds one that implicates mood as a key factor.

The other, published in JAMA Psychiatry, is much more low-tech: In face-to-face interviews, researchers asked people who were at higher than usual risk of alcoholism whether they drank to improve their mood or to calm down, and then went back two to four years later and looked at who had become, or stayed, alcohol-dependent.

Short answer: those who drank "to alleviate mood symptoms" were three times more likely to become dependent on alcohol than were those who did not use alcohol to calm themselves down or improve their mood.

Not only were the self-medicators more likely to become alcohol-dependent: among those with established alcohol dependence, those who drank to salve their emotions were less likely to have become sober than those who didn't drink to dampen painful feelings.

The brain-scan study appearing in the same issue of JAMA Psychiatry examined the working brains of 45 alcoholics in the first four to eight weeks of a 12-step program and residing at an in-patient treatment and research facility. Each recovering alcoholic was prompted to think specifically about situations that were either neutral and relaxing, or highly stressful, or were associated with past heavy drinking, while researchers watched their brain's response to each.

Alcoholics who would go on to relapse tended to show a curious and distinct pattern in their brain responses: In the relaxed, neutral condition, they showed heightened activity in a group of brain regions associated with regulation of mood and emotional arousal and cognitive control (the ventromedial prefrontal cortex, anterior cingulate cortex, the ventral striatum and the precuneus). But compared to a group of healthy control subjects, and compared to recovering alcoholics who would not go on to relapse, the relapsers showed low activity in these same regions when they were prompted to dwell on stressful situations or situations that were associated with drinking.

The cluster of brain regions that showed these upside-down patterns of response to challenging and relaxing situations is sometimes called the default mode network. It's also a cluster of regions that seems to get disrupted -- in much the same way -- in people with mood disorders.

Looking for such response patterns might help physicians and treatment facilities identify alcoholics that will need extra help in getting and staying sober, the authors of the study say. But seeing such patterns may also pave the way to a better understanding of the chicken-and-egg relationship between depression and drinking problems -- and addiction in general, wrote Dr. Nora D. Volkow, director of the National Institute on Drug Abuse, and Ruben D. Baler, a neuroscientist there, in an accompanying editorial.