Neuropeptide Y (NPY) is a naturally-occurring brain molecule that helps regulate emotional behavior, stress responses, and other functions. Much research evidence suggests that NPY also plays an important role in regulating alcohol consumption. Scientists led by NIAAA Clinical Director Markus Heilig, M.D., Ph.D., recently investigated the effect of NPY on stress-induced relapse to alcohol use. Relapse prevention is an important aspect of alcoholism treatment, and researchers who study this phenomenon often rely on animal models of relapse-like behavior. Such models usually involve training laboratory rats to obtain alcohol by pressing a lever. Later, the lever-pressing behavior is "extinguished," or unlearned, by removing the alcohol reward. Researchers then simulate alcohol relapse by exposing the animals to stress, which causes them to again seek alcohol by lever-pressing. Stress in rats is reliably induced by injections of yohimbine, a drug that causes anxiety and panic. Using this approach, Dr. Heilig and colleagues from the NIAAA Laboratory of Clinical and Translational Studies found that by injecting rats with NPY, they could suppress the relapse-like alcohol-seeking behavior brought on by yohimbine. The findings, they note, support further study of NPY as a potential treatment for alcoholism.
Neurokinin-1 receptors (NK1R) are highly expressed in brain areas involved in stress responses and drug reward. In recent years, mounting research evidence has suggested that they may help regulate important aspects of alcohol use. In a new study, researchers at the NIAAA report that a compound that blocks NK1R suppresses alcohol drinking in mice. NIAAA Clinical Director Markus Heilig, M.D., Ph.D., and colleagues from the NIAAA Laboratory of Clinical and Translational Studies also showed that mice that lack the gene for NK1R have a lower preference for alcohol than do normal mice, and score lower on measures of alcohol reward, a key aspect of its addictive effects. Taken together, the data from the new study supports further investigation of NK1R blockade as a potential treatment for alcoholism.
Drinking may harm adolescents' ability to concentrate and to understand spatial relationships. A recent study led by Susan Tapert at the University of California, San Diego compared the standardized test scores of 76 12 to 14 year old kids with their scores after about three years. At the three-year follow-up, 36 of the kids had begun drinking at moderate to heavy levels and 40 continued not using alcohol or other drugs. The study defined moderate to heavy drinking as drinking at least monthly and having three or more drinks at a time, or drinking less frequently, but having four or more drinks at a time. The kids in this study were consuming an average of about eight drinks per month by the time they reached the follow-up.
During the study's three-year time period, the team discovered once teens began to drink, they performed more poorly on cognitive tests than before they began drinking. Interestingly, the kinds of skills affected varied between girls and boys.
The researchers found that girls' scores on tasks requiring them to visualize and reproduce a complicated line drawing decreased after they began drinking. The researchers also found that boys' scores on tests requiring sustained attention decreased after they began drinking.
Tapert's study suggests that these behavioral effects may point toward alcohol's underlying effect on brain structure. Brain scans demonstrate that adolescent drinking can reduce the health of white matter in the brain. White matter is where brain cells communicate with each other, so damage to this area can result in slower, less efficient thinking. Reduced white matter integrity may cause girls to have difficulty understanding spatial relationships. This damage may be long-lasting since the adolescent brain is still undergoing significant developmental changes, making it especially vulnerable to alcohol's toxic effects.
Also see: Altered white matter integrity in adolescent binge drinkers, McQueeny T, Schweinsburg BC, Schweinsburg AD, Jacobus J, Bava S, Frank LR, & Tapert SF, Alcoholism: Clinical and Experimental Research, 2009, 33, 1278-1285.
A new analysis has shown that combined behavioral intervention (CBI), counseling that integrates cognitive-behavioral therapy, motivational enhancement, and techniques to enhance mutual help group participation, used alone in conjunction with naltrexone, a drug approved to help treat alcoholism, can reduce drinking in alcohol-dependent individuals. In this reanalysis of data from the COMBINE Study—the largest pharmacotherapy trial for alcoholism in the United States—researchers identified clinically useful trajectories of drinking (abstainers, infrequent drinkers, frequent to infrequent drinkers, increasing to frequent drinkers, increasing-to-nearly daily drinkers, and nearly daily drinkers). In addition, researchers determined that naltrexone reduced the chance that participants would follow a nearly daily drinking trajectory, and that CBI reduced participants' chance of following an increasing to nearly daily trajectory. Combining naltrexone and CBI, however, increased the chance of membership in a trajectory with a declining frequency of any drinking over time.
Because original COMBINE analysis showed no treatment advantage for naltrexone plus CBI, the researchers believe that trajectory analysis of COMBINE data provide a more complete representation of drinking during treatment and the effects of treatments on different aspects of drinking. These results reveal that certain subgroups of individuals may benefit more from specific treatments than is apparent from summary measures of COMBINE data.
Brief counseling sessions by physicians can help college students reduce harmful alcohol use, according to a new study supported by NIAAA. Led by Michael F. Fleming, M.D., M.P.H., of the University of Wisconsin, the study is part of the ongoing College Health Intervention Projects (CHIPs) study, a randomized, controlled clinical trial conducted in five college health clinics in Wisconsin, Washington state, and Vancouver, Canada. College health service clinicians examined whether brief counseling sessions would reduce the rates of heavy alcohol use and alcohol-related harm among the nearly 1,000 heavy-drinking students enrolled in the study. After a 12 month follow-up period, alcohol consumption had reduced in the experimental group by 27.2%, compared with a 21% reduction among students in a control group. Heavy episodic drinking also declined by 26.3% in the experimental group, and 23.3% in the control group. This study adds to growing evidence that college health clinic visits are "teachable moments" during which clinicians can help address harmful alcohol use by students.